NILFISK SC1500-X20D Service Manual

SC1500

Service Manual

Advance SC1500 Models: 56104000 (X20D), 56104001 (X20R)

Nilsk SC1500 Models: 56104002 (SC1500-51D)

English

5/13 Form No. 56043166

Contents

General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Machine Congurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Service Manual Purpose and Application . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Other Reference Manuals and Information Sources . . . . . . . . . . . . . . . . . . . . 6

Diagnostic and Service Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Parts and Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Modications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Nameplate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Cautions and Warning Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

General Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Prop Rod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Moving the Machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

Transporting the Machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

General Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Overall Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Fastener Torque Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Lubrication Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Major Machine Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

Machine Controls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

iiService Manual – SC1500

General Maintenance Information . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Maintenance Schedule. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

Key Switch, Emergency Stop and Horn Switch . . . . . . . . . . . . . . . . . . . .16

Circuit Breakers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Speed and Direction Controls and Indicators. . . . . . . . . . . . . . . . . . . . . .18

Scrub Controls and Indicators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19

Solution Controls and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . .20

Detergent System Controls and Indicators . . . . . . . . . . . . . . . . . . . . . . .20

Burst of Power Switch and Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Vacuum Power Adjustment Switch and Indicators . . . . . . . . . . . . . . . . . .22

Information Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Battery Status and Charger Screens . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Chassis System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Major Chassis Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Platform Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26

Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Functional Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

Component Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Fault Codes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28

Fault Code Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29

System Disabled by Fault Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Service Test Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

To Access the Service Test Mode . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Service Test Mode Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

To Exit the Service Test Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Programming Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

To Access the Main Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

To Access a Submenu from the Main Menu . . . . . . . . . . . . . . . . . . . . . . 35

To Change a Programmable Option in a Submenu . . . . . . . . . . . . . . . . . .35

Deck Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Low Battery Voltage Cutout . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Battery Charger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

Burst Of Power Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

Detergent (EcoFlex™) Option . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

Chemical Rate Bias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

Open Fault Detect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38

Display Rev Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38

Lock Out Brush Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Lock Out Solution Flow Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Backup Alarm Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Forward Alarm Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40

Horn Volume. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40

Restore Defaults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

Fault Recall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Service Test Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

Extra Information on the Graphic Display . . . . . . . . . . . . . . . . . . . . .42

Frozen Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Panel Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Save Scrub Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

Removal and Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

A1 Control Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

E1 Curtis 1210 Speed Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

A1 Control Board Shop Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Contents iiiService Manual – SC1500

Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

On-board Battery Charger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

Battery Charger Circuit Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . .54

Battery Charger Not Plugged In . . . . . . . . . . . . . . . . . . . . . . . . . .54

Battery Charger Plugged In. . . . . . . . . . . . . . . . . . . . . . . . . . . . .55

Component Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Electrical Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Wiring Diagram, p/n 56104081, Rev. B, Page 1 . . . . . . . . . . . . . . . . . . . . 58

Wiring Diagram, p/n 56104081, Rev. B, Page 2 . . . . . . . . . . . . . . . . . . . . 59

Wiring Harness Diagram, p/n 56104082, Rev. B . . . . . . . . . . . . . . . . . . . .60

Electrical Connector Pin-out Assignments . . . . . . . . . . . . . . . . . . . . . . . . . 61

To Locate and Identify a Connector . . . . . . . . . . . . . . . . . . . . . . . . . . .61

Connector Pin-out Assignment Tables . . . . . . . . . . . . . . . . . . . . . . . . .62

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69

Recovery System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Functional Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70

Circuit Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71

Vacuum Motor Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71

Vacuum Motor On . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Component Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Removal and Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Vacuum Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77

Special Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77

Scrub System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Functional Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78

Scrub Deck and Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79

20D Scrub Deck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

20R REV™ Deck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80

Brush Motor Contactor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81

Deck Actuator Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81

Circuit Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83

Scrub Brush Motor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83

Scrub Brush Motor Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

Scrub Brush Motor On . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84

Deck Actuator Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85

Scrub Deck Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85

Scrub Deck in Vacuum-only Position . . . . . . . . . . . . . . . . . . . . . . . .85

Scrub Deck at Normal Scrub Pressure . . . . . . . . . . . . . . . . . . . . . . .86

Scrub Deck at Extra Scrub Pressure . . . . . . . . . . . . . . . . . . . . . . . . 86

Component Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

Removal and Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

Scrub Deck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90

Scrub Deck Actuator Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

Scrub Deck Actuator Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96

Contents ivService Manual – SC1500

Solution System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Functional Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97

Solution Tank, Water Filter and Valves . . . . . . . . . . . . . . . . . . . . . . . . 97

Solution Solenoid Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98

Detergent System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

Circuit Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

Solution Solenoid Valve Off . . . . . . . . . . . . . . . . . . . . . . . . . . . .100

Solution Solenoid Valve On . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

Detergent Pump Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102

Detergent Pump On . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

Component Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

Cleaning the Water Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108

Component Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

Nominal Solution Flow Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

Squeegee System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

Functional Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110

Component Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112

Steering System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113

Functional Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113

Component Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

Wheel System - Traction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116

Functional Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116

Wheel Drive Motor Circuit Descriptions . . . . . . . . . . . . . . . . . . . . . . . 117

Power to the E1 Curtis 1210 Speed Controller. . . . . . . . . . . . . . . . . .117

Speed Control Drive Functions . . . . . . . . . . . . . . . . . . . . . . . . . . 118

Speed Control Communication with the A1 Control Board . . . . . . . . . . . 119

Component Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

Maintenance and Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

Speed Control Programming Options . . . . . . . . . . . . . . . . . . . . . . . . . 123

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

General Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

E1 Curtis Speed Controller Diagnostics . . . . . . . . . . . . . . . . . . . . . . . 124

Diagnostics Method A - Graphic Display and Detergent On/Off Indicator . . . 124

Diagnostics Method B - Curtis Programmer . . . . . . . . . . . . . . . . . . . 125

Diagnostic History. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125

Status LED Fault Code Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126

Removal and Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

Drive Wheel Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .127

Drive Wheel Motor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .129

Steering Spindle Bearings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131

Drive Wheel Motor Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

Replacing the Motor Brushes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134

Shop Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

E1 Curtis 1210 Speed Controller – Low Current . . . . . . . . . . . . . . . . 134

E1 Curtis 1210 Speed Controller – Output. . . . . . . . . . . . . . . . . . . .135

General Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135

Special Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

Contents vService Manual – SC1500

General Information

Machine Congurations

The SC1500 machines are battery-powered commercial oor scrubbing machines suitable for use in hotels,
schools, hospitals, factories, shops, ofces, rental businesses and similar applications.

The SC1500 is available in two scrub system congurations:

• The 20D models have a 20” brush plate assembly to accommodate a variety of disc brushes. The 20D
models can also be used with several grades of pads by using the optional pad holder.

• The 20R models have a 20” REV™ scrub system that uses a pad driver for use with REV™ deck pads only.

The machine is powered by either four 6-volt batteries or two 12-volt batteries, connected in series, to
provide 24 VDC to the motors and controls.

Service Manual Purpose and Application

6Service Manual – SC1500

This Service Manual is a technical resource designed to aid service personnel in maintaining and repairing
the Advance SC1500 Scrubbers to ensure optimum performance and long service life. Please read it
thoroughly before servicing your machine.

Other Reference Manuals and Information Sources

Model Name Model Number

Advance SC1500 56104000, 56104001 56042591
Nilsk SC1500 56104002 (SC1500-51D) 56042592

These manuals can be found on the following Nilsk-Advance’s electronic supported databases:

• Nilsk-Advance Dealer Customer Zone

• Advance website: www.advance-us.com

• Nilsk website: www.nilsk.com

• EzParts service/parts CD-ROM

Parts List

Form Number

Instructions for Use

Form Number

56091047 - English, Español,
Français Português

Diagnostic and Service Tools

In addition to a full set of metric and standard tools, the following items are required in order to successfully
and quickly perform troubleshooting and repair of Advance commercial oor cleaning equipment.

• Digital voltmeter (DVM) with DC current clamp

• Hydrometer

• Battery load tester for checking batteries

• Set of torque wrenches

General Information 7Service Manual – SC1500

These tools are also available from Nilsk-Advance, Inc.:

• Curtis 1311 hand held programmer, p/n 56409441,

• Vacuum water lift gauge, p/n 56205281.

Conventions

All references to right, left, front and rear in this manual are as seen from the Operator’s position.

Parts and Service

Repairs should be performed by an Authorized Advance Service Center that employs factory-trained service
personnel and maintains an inventory of Advance original replacement parts and accessories.

Call the Advance Dealer named below for repair parts or service. Please specify the Model Number (same as
the Part Number) and Serial Number when discussing your machine.

(Dealer, afx service sticker here.)

Modications

Modications and additions to the cleaning machine which affect capacity and safe operation shall not be
performed by the customer or user without prior written approval from Nilsk-Advance Inc. Unapproved
modications will void the machine warranty and make the customer liable for any resulting accidents.

Nameplate

The Model Number and Serial Number of the machine are
shown on the Nameplate located on the inside of the battery
compartment.

This information is needed when ordering repair parts for the
machine.

General Information 8Service Manual – SC1500

Cautions and Warning Symbols

Nilsk-Advance uses the symbols below to signal potentially dangerous conditions. Read this information
carefully and take the necessary steps to protect personnel and property.

Danger! Is used to warn of immediate hazards that will cause severe personal injury or death.

Warning! Is used to call attention to a situation that could cause severe personal injury.

Caution! Is used to call attention to a situation that could cause minor personal injury or

damage to the machine or other property.

Read all instructions before using.

General Safety Instructions

Specic Cautions and Warnings are included to warn you of potential danger of machine damage or bodily
harm. This machine is for commercial use, for example in hotels, schools, hospitals, factories, shops and
ofces other than normal residential housekeeping purposes.

Warning! Be sure to follow these safety precautions to avoid situations that could cause

severe personal injury.

• This machine should only be used by properly-trained and authorized personnel.

• This machine is not intended for use by persons (including children) with reduced physical,
sensory or mental capabilities, or lack of experience and knowledge.

• Avoid sudden stops when on ramps or inclines. Avoid abrupt sharp turns. Use low speed down
ramps.

• Observe the Gross Vehicle Weight, GVW, of the machine when loading, driving, lifting or
supporting the machine.

• Keep sparks, ame and smoking materials away from batteries. Explosive gases are vented
during normal operation.

• Charging the batteries produces highly-explosive hydrogen gas. Charge the batteries only in
well-ventilated areas away from open ame. Do not smoke while charging the batteries.

• Remove all jewelry when working near electrical components.

• Turn the Key Switch off (O) and disconnect the batteries before servicing electrical components.

• Never work underneath a machine without safety blocks or stands to support the machine.

• Do not dispense ammable cleaning agents, operate the machine on or near these agents, or
operate in areas where ammable liquids exist.

General Information 9Service Manual – SC1500

• Only use the brushes provided with the machine or those specied in the Instructions for Use.
The use of other brushes may impair safety.

• Do not clean this machine with a pressure washer.

Caution! Be sure to follow these safety precautions to avoid situations that could cause

personal injury, damage to property or equipment damage.

• This machine is not approved for use on public paths or roads.

• This machine is not suitable for picking up hazardous dust.

• Do not use scarier discs and grinding stones. Advance will not be held responsible for any
damage to oor surfaces caused by scariers or grinding stones (can also cause damage to the
brush drive system).

• When operating this machine, ensure that individuals in close proximity, particularly children,
are not endangered.

• Before performing any service function, carefully read all instructions pertaining to that
function.

• Do not leave the machine unattended without rst turning the Key Switch off (O), removing the
key and applying the parking brake.

• Turn the Key Switch off (O) and remove the key before changing the brushes, and before
opening any access panels.

• Take precautions to prevent hair, jewelry or loose clothing from becoming caught in moving
parts.

• Use caution when moving this machine in below-freezing temperature conditions. Any water in
the solution, recovery or detergent tanks, or in the hose lines could freeze, causing damage to
valves and ttings. Flush with windshield washer uid.

• The batteries must be removed from the machine before the machine is scrapped. The disposal
of the batteries should be safely done in accordance with your local environmental regulations.

• Do not use on surfaces having a gradient exceeding that marked on the machine.

• All doors and covers are to be positioned as indicated in the Instructions for Use before using
the machine.

• This machine should only be used and stored indoors.

Caution! Do not clean this machine with a pressure washer.

Prop Rod

To prevent the Control Panel Housing / Recovery

Tank Cover

causing injury, always engage the Prop Rod as
shown before working under the Panel Housing

/ Recovery Tank Cover

from dropping unexpectedly and

.

General Information 10Service Manual – SC1500

Control Panel

Housing/

Recovery

Tank Cover

Prop Rod

(engaged)

Moving the Machine

The drive wheel motor has a built-in
electromagnetic brake that engages whenever
the Key Switch is Off or the Go Pedal is
released. You can manually override this
brake if necessary by reaching up around the
back of the front drive wheel and rotating the

Brake Arm up as shown. This should only be

done if you need to push or pull the machine.
Remember to reengage the Brake Arm once you
nish moving the machine.

Note: Turn the drive wheel 45° to

the right for easier access to
the Brake Arm.

Brake

Arm

Brake

Arm

Transporting the Machine

Caution! Before transporting the machine on an open truck or trailer, make sure:

• All tanks are empty.

• The recovery tank cover is latched securely.

• The machine is tied down securely. (Refer to the Tie-down Locations below.

• The machine’s electromagnetic brake is engaged (not manually overridden).

General Information 11Service Manual – SC1500

Left

Tie-down

Front

Tie-down

Right

Tie-down

Specications

General Specications

Model SC1500-X20D SC1500-X20R

Model No. 56104000 56104001
Battery Voltage 24V
Battery Capacity - Amp Hours 260
Protection Grade IPX3
Sound Pressure Level IEC 60335-2-72: 2002 Amend.

1:2005, ISO 11201 dB(A)

Gross Vehicle Weight (w/full solution tank, empty
recovery tank, heaviest batteries, no Operator

Net Weight ((w/empty solution and recovery tanks, no
batteries or brushes

Maximum Operator/Rider Weight 250 lbs / 113.4 kg
Scrub Deck Width 20 in / 50.8 cm

Squeegee Width 26.5 in / 67.3 cm

Tank Capacities

Static Wheel Loading with 179 lb. rider Front: 362 lbs / 164 kg Rear: 275 lbs / 125 kg

Static Wheel Pressure with 175 lb. rider Front: 116 psi / 8.2 kg/cm

Sound Pressure Level (IEC 60704-1)TR12116 63.33 dB(A)/.029344 µPa

Vibrations at the Hand Controls (ISO 5349-1) <.5 m/s
Vibrations at the Seat (EN 1032) <2.5 m/s2

Gradeability

63 dB LpA, ±3 dB KpA 62 dB LpA, ±3 dB KpA

718 lbs / 326 kg

354 lbs / 161 kg

Solution Tank: 11.7 gal / 44.28 L

Recovery Tank: 13.5 gal / 46.67 L

2

Rear: 139 psi / 9.8 kg/cm

2

Transport: 14.5 percent / 8.2 degrees

Cleaning: 8.0 percent / 4.5 degrees

2

Overall Dimensions

1.13
[28,7]

1.13”
[28,7 mm]

General Information 12Service Manual – SC1500

48.5

48.5” [123,2 cm]

[1232]

Fastener Torque Specications

Size Plated Steel Stainless Steel

#10 42 in.-lb. [4.75 N-m] 28 in.-lb. [3.17 N-m]
1/4“ 100 in.-lb. [11.3 N-m] 67 in.-lb. [7.57 N-m]

5/16” 17 ft.-lb. [23.05 N-m] 11 ft.-lb. [14.91 N-m]

3/8” 31 ft.-lb. [42.03 N-m] 20 ft.-lb. [27.12 N-m]

Standard Torque

Specications (unless
otherwise specied)

1/2” 75 ft.-lb. [101.69 N-m] 50 ft.-lb. [67.79 N-m]
3/4” 270 ft.-lb. [366.07 N-m] 180 ft.-lb. [244.05 N-m]

M5 61 in.-lb. [6.89 N-m] 36 in.-lb. [4.07 N-m]
M6 9 ft.-lb. [12.2 N-m] 62 in.-lb. [7.0 N-m]

M8 22 ft.-lb. [29.83 N-m] 13 ft.-lb. [17.63 N-m]
M10 44 ft.-lb. [59.66 N-m] 25 ft.-lb. [33.9 N-m]
M12 70 ft.-lb. [94.91 N-m] 40 ft.-lb. [54.23 N-m]

52.5”

52.5
[1332]

[133,4 cm]

24.5

24.5” [62,2 cm]

[623]

27.9

27.9” [70,9 cm]

[710]

General Information 13Service Manual – SC1500

Maintenance

General Maintenance Information

Keep the machine in top condition by closely following the maintenance schedule. Maintenance intervals
given are for average operating conditions. Machines used in severe environments may require service more
often.

Caution! Do not pressure-wash the machine

Maintenance Schedule

Maintenance Item Daily Weekly Monthly Yearly

Charge Batteries X

Check/Clean Tanks & Hoses X

Check/Clean the Brushes/Pads X

Check/Clean the Squeegee X

Check/Clean Vacuum Shutoff Float X

Empty/Clean Debris Catch Tray in Recovery Tank X

Check Each Battery Cell(s) Water Level X

Inspect Scrub Housing Skirt X

Inspect and Clean Solution Filter X

Purge Detergent System X

Lubricate Machine X

* Check Carbon Brushes X

** Replace vibration damping isolators (REV model only) X

* Have an Authorized Advance Service Center check the vacuum motor carbon motor brushes once a year or

after 300 operating hours. The brush and drive motor carbon brushes should be checked every 500 hours
or once a year.

** This maintenance procedure must be performed by an authorized Advance Service Center.

General Information 14Service Manual – SC1500

Lubrication Locations

• Once a month apply Lubriplate® 730-2 or equivalent grease to, or grease the tting on, the following
components. Avoid using too much grease.

– Hex Shaft/Steering Tube Assembly
– Drive Wheel Chain

– Drive Chain Idler Sprocket (grease tting)
– Steering Chain

• Once a month apply light machine oil to the Upper and Lower Steering Shaft Universal Joints.

Upper

Steering

Shaft

U-Joint

Hex

Shaft

Steering

Tube

Assembly

Lower Steering

Steering

Chain

Shaft U-Joint

Drive Chain

Idler

Sprocket

(grease

tting)

Drive

Wheel

Chain

Major Machine Components

Control
System

General Information 15Service Manual – SC1500

Electrical

System

Solution

System

Recovery

System

Chassis

System

Squeegee
Assembly

Scrub

System - 20D

Scrub

System - REV

Machine Controls

Key Switch, Emergency Stop and Horn Switch

• Key Switch – controls the battery power to the machine.
Note that you must turn the Key Switch to the on (I)
position before stepping onto the machine platform.

General Information 16Service Manual – SC1500

Key

Switch

• Emergency Stop – shuts off all battery power to the
machine when pressed. To reset the Emergency Stop, rotate
the red knob clockwise.

• Horn Switch – sounds the horn when pressed.

Emergency

Stop

Horn

Switch

General Information 17Service Manual – SC1500

Circuit Breakers

The Circuit Breakers are mounted on the top of the control panel. To reset a Circuit Breaker, press the
corresponding reset button

• 50-amp Circuit Breaker – labeled CB1 in the
Ladder Diagram; controls the positive voltage
to the E1 Curtis 1210 Speed Controller.

• 5-amp Circuit Breaker – labeled CB2 in the
Ladder Diagram; controls the positive voltage
to the key switch and to the battery positive
inputs J3-1 and J3-8 on the A1 Control Board.

• 20-amp Circuit Breaker – labeled CB3 in the
Ladder Diagram; controls the positive voltage
to the contacts on solid state relay K1. Relay
K1 controls the positive voltage to the vacuum
motor, M4.

• 25-amp Circuit Breaker – labeled CB4 in the
Ladder Diagram; controls the positive voltage
to the contacts on relay K2. Relay K2 controls
the positive voltage to the brush motor, M5/M6.

50-amp

Circuit

Breaker CB1

20-amp

Circuit

Breaker CB3

5-amp

Circuit

Breaker CB2

25-amp

Circuit

Breaker CB4

General Information 18Service Manual – SC1500

Speed and Direction Controls and Indicators

• The Speed Adjustment Knob – labeled R1 in the Ladder Diagram;
100K potentiometer that controls the machine speed in both
forward and reverse.

• The Forward and Reverse Drive Switches select the direction the machine will move when the Go Pedal is
pressed. The corresponding Drive Indicator will light when a Drive Switch is selected.

– Forward Drive Switch – selects the forward direction.

Forward Drive

– Forward Drive Indicator – lights to indicate that the

Forward Drive Switch has been selected. Note that this

indicator is lighted in the adjacent drawing.

– Reverse Drive Switch – selects the reverse direction.

Speed

Adjustment

Knob R1

Indicator

Forward

Drive Switch

– Reverse Drive Indicator – lights to indicate that the

Reverse Drive Switch has been selected.

• Operator Presence Pedal – ensures
that the Operator is standing on
the Platform before the Go Pedal
will drive the machine forward or
reverse.

• Go Pedal – drives the machine in
the direction selected with the
Forward Drive or Reverse Drive
Switches.

Reverse

Drive Switch

Reverse Drive

Indicator

Go

Pedal

Operator

Presence

Pedal

Platform

Scrub Controls and Indicators

Note: Thescrubpressure,recoveryvacuumpower,solutionowrateanddetergentstrength

settings that will be in effect when the One-touch™ Scrub On/Off Switch is pressed is
determined by the Save Scrub Settings submenu in the Programming Options.

• IfSAVE SCRUB SETTINGS/YES is selected, the machine will use the scrub settings that
were in use when the key switch was switched off.

• IfSAVE SCRUB SETTINGS/NO is selected, the machine will use the default settings.

(Refer to the Save Scrub Settings subsection in the Control System section.)

General Information 19Service Manual – SC1500

• One-touch

™

Scrub On/Off Switch – lowers the scrub deck and

squeegee to the oor and enables the scrub, vacuum, solution
and detergent systems. The scrub motor, solution system,
detergent pump and vacuum motor will start when you press
the Go Pedal.

• Scrub On/Off Indicator – lights to indicate that the scrub system

is active.

• Extra Pressure Switch – toggles the scrub pressure

between standard pressure (bottom box lled as
shown) and extra pressure (both top and bottom
boxes lled).

• Extra Pressure Indicator – lights to indicate that the

scrub system is active.

• Scrub Brush Pressure Bar Graph – displays the

scrub pressure on the graphic display as follows:

– Bottom box lled – standard scrub pressure (as

shown).

– Top and bottom boxes lled – extra scrub

pressure.

Scrub On/Off

Indicator

One-touch™

Scrub On/Off

Switch

Scrub

Pressure

Bar Graph

Extra

Pressure

Switch

Extra
Pressure
Indicator

General Information 20Service Manual – SC1500

Solution Controls and Indicators

• Solution Flow Adjustment Switch – functions as follows:
– When the scrub system is enabled, pressing the Solution

Flow Adjustment Switch

will cycle the solution ow rates
from low (bottom box lled as shown), to medium (bottom
two boxes lled), to high (all three boxes lled), then to off
(no boxes lled).

– When the scrub system is not enabled (machine in

transport mode), pressing and holding the Solution Flow

Adjustment Switch

will dispense solution at the high ow

rate to pre-wet the oor. The solution will continue to
dispense as long as the Solution Flow Adjustment Switch is
pressed.

• Solution On/Off Indicator – lights to indicate that the solution system is active.

• Solution Flow Rate Bar Graph – displays the solution ow rate on the graphic display as follows:

– Bottom box lled – low solution ow rate (as shown).

Solution

Flow Rate

Bar Graph

Solution On/Off

Indicator

Solution

Flow Adjustment

Switch

– Bottom two boxes lled – medium solution ow rate.

– All three boxes lled – high solution ow rate.

– All three boxes empty – solution system off.

Detergent System Controls and Indicators

• Detergent Strength Switch – functions as follows:

– When the scrub system is enabled, pressing

the Detergent Strength Switch will cycle the
detergent ow rate from weak (bottom box
lled as shown), to strong (top and bottom
boxes lled), then to off (no boxes lled).

Detergent On/Off

Indicator

– When the scrub system is not enabled

(machine in transport mode), pressing
and holding the Detergent Strength Switch

Detergent

Strength Switch

and Solution Flow Adjustment Switch
simultaneously will enable the purge mode.

• Detergent On/Off Indicator – indicates that the detergent ow rate is a rate other than zero.

• Detergent Indicator Bar Graph – displays the detergent ow rate, ratio and percentage on the graphic

display as follows:

Detergent

Indicator

Bar Graph

– Bottom box lled – weak detergent ow rate (as shown).

– Top and bottom boxes lled – strong detergent ow rate.

– Both boxes empty – detergent system off.

• Detergent Purge Screen – displays the Chemical Purge Icon to

indicate that the detergent purge cycle is active. To start
the purge cycle and display the Detergent Purge Screen, press
and hold the Detergent Strength Switch and the Solution Flow
Adjustment Switch simultaneously for three seconds. The

Detergent On/Off Indicator will ash and the purge cycle will last

for approximately 10 seconds.

Burst of Power Switch and Indicator

General Information 21Service Manual – SC1500

Chemical

Purge

Icon

Detergent Purge Screen

• Burst of Power Switch – temporarily overrides the current machine

settings to increase the machine’s cleaning aggressiveness by
performing the following:

– Increases the scrub pressure from standard pressure to extra

pressure.

Burst of Power

Indicator

Burst of

Power Switch

– Increases the solution ow rate by one level (off to low, low to

medium or medium to high).

– Increases the detergent ow rate to the strong level (off to

weak or weak to strong). Note that this will only happen if the
detergent option is installed.

– Increases the vacuum power from low/quiet to high/standard. Note that the vacuum motor will not

switch from off to low/quiet because of the assumption that if the vacuum is off, the user must be in
double-scrubbing mode and wishes to stay in that mode.

If any one of the functions listed above is already performing at its maximum possible rate, the Burst of

Power Switch

will have no effect on that function but will still affect the other functions. If the detergent
option is not installed, the Burst of Power will not affect detergent ow but will still affect the other
functions.

The Burst of Power mode lasts for a maximum duration of 60 seconds but can be terminated early by
pressing the Information Switch, Burst of Power Switch, Scrub On/Off Switch, Detergent Strength Switch,
Solution Flow Adjustment Switch, Extra Pressure Switch or the Vacuum Power Adjustment Switch.

When the Burst of Power period expires or is terminated, all scrubbing parameters that were changed
return to their original state before the Burst of Power Switch was pressed.

• Burst of Power Indicator – indicates the following:
– The Burst of Power Indicator will be off when the Burst of Power Switch switch is not functional because

it has not been enabled in the Hidden Menu, or because the machine is operating in a mode for which
the Burst of Power option does not apply.

– The Burst of Power Indicator will be solid green when the machine is operating in a reduced/normal

scrubbing mode but the Burst of Power option is available.

– The Burst of Power Indicator will change color from green to yellow and ash for 60 seconds while the

Burst of Power option is active. The Burst of Power Indicator will ash at a rate of 1 Hz for the rst 50
seconds, then at a rate of 2 Hz for the last 10 seconds to indicate that the Burst of Power option is
about to end.

Vacuum Power Adjustment Switch and Indicators

• Vacuum Power Adjustment Switch – functions as

follows:

– Pressing the Vacuum Power Adjustment

Switch

while in the scrub mode will cycle

Quiet

Vacuum

Mode

Indicator

the vacuum mode from low/quiet (bottom
box lled as shown), to high/standard (both
top and bottom boxes lled), then to off (no
boxes lled). Note that the vacuum motor
will switch on when the machine is driven
forward. When the machine is driven in
reverse or stops, or if the Vacuum Power

Adjustment Switch

is pressed while the
vacuum motor is running, the vacuum motor
will continue to run for 10 seconds, then
switch off.

Pressing the Vacuum Power Adjustment Switch during this 10-second delay period will shut off the
vacuum motor immediately.

Vacuum

Level Bar

Graph

Standard Vacuum

Mode Indicator

Vacuum Power

Adjustment

Switch

General Information 22Service Manual – SC1500

– When the scrub system is not enabled (machine in transport mode), the Vacuum Power Adjustment

Switch

functions as follows:

◦ Pressing the Vacuum Power Adjustment Switch once will enable the wet vacuuming mode. The

vacuum power will default to the low/quiet mode and the deck actuator will drive the deck to the
“vacuum only” position.

◦ Pressing the Vacuum Power Adjustment Switch a second time will switch the vacuum motor to high/

standard mode.

◦ Pressing the Vacuum Power Adjustment Switch a third time will disable the wet vacuuming mode.

The actuator will immediately raise the deck, and the vacuum motor will turn off after a 10-second
delay.

Note: IftheOne-touch™ Scrub On/Off Switch is pressed while wet vacuuming, the wet vacuuming

mode will be disabled. The scrub deck and vacuum motor control will revert to the standard
scrub mode operation.

• Quiet Vacuum Mode Indicator – indicates that the vacuum motor is in the low/quiet mode.

• Standard Vacuum Mode Indicator – indicates that the vacuum motor is in the high/standard mode.

• Vacuum Level Bar Graph – displays the vacuum motor power mode as follows:

– Bottom box lled – low/quiet mode (as shown).

– Top and bottom boxes lled – high/standard mode.

– Both boxes empty – vacuum motor off.

Information Switch

General Information 23Service Manual – SC1500

• Information Switch – displays the Information Screen on the

graphic display. The Information Screen will also be displayed
if a signicant error occurs that results in the shutdown of
some machine system. The graphic display will then display

Hour

Meter

Fault

Codes

the Information screen until next key switch cycle.
The Information Screen shows the Hour Meter, Fault Codes and

the Battery Charge Level Indicator.

• Hour Meter – displays the total number of run hours on the

machine.

• Fault Codes – displays the wrench icon and any active

two-digit fault code. If more than one error exists, the display
will sequence through the error codes at one-second intervals.

(Refer to the Fault Codes subsection in the Control System

Battery

Charge Level

Indicator

Information

Switch

section.)

• Battery Charge Level Indicator – indicates the charge level of the batteries according to the number of lled

“bars” in the battery icon.

– Five solid bars indicates a full battery charge.

– No solid bars (empty battery icon) indicates that the batteries are discharged.

Battery Status and Charger Screens

• Battery Low Voltage Screen – displayed when the battery

voltage drops to approximately 21.75 volts. The graphic
display will alternate between the Battery Status Screen
and the “normal” display at ve-second intervals to alert the
Operator that the batteries need charging and the remaining
battery time is very short.

Note that:

– When the voltage in AGM or Gel batteries drops to 21.75 volts, the A1 Control Board switches off the

scrub motor, solution system and detergent pump, and raises the scrub deck. The vacuum motor can
still remain on.

– When the voltage in AGM or Gel batteries drops to 21.6 volts, the A1 Control Board switches off the

vacuum motor.

– When the voltage in Wet batteries drops to 20.55 volts, the A1 Control Board switches off the scrub

motor, solution system and detergent pump, and raises the scrub deck. The vacuum motor can still
remain on.

– When the voltage in Wet batteries drops to 20.4 volts, the A1 Control Board switches off the vacuum

motor.

Battery Low Voltage Screen

• Battery Charger Screen – displayed when AC power is applied

to the onboard charger. Note that this will disable all
machine functions. The Battery Charger Screen displays the

Battery Type and Battery Charge Level Indicator. The Battery
Charge Level Indicator

will display full once the batteries are

done charging.

General Information 24Service Manual – SC1500

Battery

Type

Battery Charge
Level Indicator

Battery Charger Screen

Chassis System

Major Chassis Components

The Chassis System provides the framework on which the machine components are mounted.
The Battery Tray

contains the batteries
and connectors and is
mounted to the top of
the Chassis Weldment.

The Platform Assembly
provides a place for the
Operator to stand and
houses the Operator
Presence Pedal and Go
Pedal.

The Battery Charger
is mounted to the
bottom of the Chassis

Weldment

.

The non-traction

Wheels are held by at

washers and M8 x 20
screws that thread into
the axle in the Chassis

Weldment

.

The Drive Wheel

Assembly

is fastened

to the Spindle Mount

Weldment

which

bolts to the Chassis

Weldment

.

Battery

Tray

Chassis

Weldment

Spindle

Mount

Weldment

Battery

Charger

Link Bar

Platform

Assembly

Wheel (2)

Linkage

Bar (2)

25Service Manual – SC1500

The Link Bar and the
two Linkage Bars are
bolted to vertical
plates on the bottom of
the Chassis Weldment
and support the Scrub
Deck.

Drive

Wheel

Assembly

Chassis System 26Service Manual – SC1500

Platform Switches

The Operator Presence Pedal and Go Pedal are mounted on the top of the Platform.

• When the Operator stands on the Platform, he/she presses the Operator Presence Pedal which actuates the

Operator Presence Switch (called the “Deadman Switch S2” in the Wiring Diagram). The Operator Presence
Switch

must be actuated before the Go Pedal will drive the machine forward or reverse.

• When the Operator presses the Go Pedal it actuates the Go Switch to drive the machine in the direction

selected with the Forward Drive or Reverse Drive Switches.

Go Switch

Go Pedal

Operator

Presence

Switch

Platform

Operator
Presence

Pedal

Control System

Functional Description

The Control System consists of the A1 Control Board (Main Machine Controller) and the E1 Curtis 1210
Speed Controller.

The A1 Control Board controls the scrubbing and wastewater recovery functions based on Operator requests,
and motion and direction inputs from the E1 Curtis 1210 Speed Controller. The A1 Control Board can store
and display a variety of fault codes to inform the Operator of any machine fault conditions. The A1 Control
Board also supports special modes of operation called the “Programming Mode” and the “Service Test Mode”.
The Programming Mode is used primarily for “telling” the A1 Control Board how the machine is equipped so
that it can operate accordingly. The Service Test Mode allows you to operate various machine components
regardless of current inputs.

The E1 Curtis 1210 Speed Controller controls the drive motor that propels the machine based on Operator
requests. (Refer to the Wheel System, Traction section for more information.)

27Service Manual – SC1500

Component Locations

The following components are included in
this section:

• A1 Control Board

• E1 Curtis 1210 Speed Controller

The A1 Control Board is mounted to the
rear of the Interface Panel Assembly.

The E1 Curtis 1210 Speed Controller is
mounted inside of the Control Panel.

Interface

Panel

Assembly

A1 Control

Board

Control System 28Service Manual – SC1500

E1 Curtis

1210 Speed

Controller

Control

Panel

Troubleshooting

Fault Codes

The graphic display will show any error codes detected by
the A1 Control Board on the Information Screen as they
occur. The display will show the wrench icon and the
two-digit fault code number. The example shown here, 03,
is a speed control fault.

If more than one fault exists, the display will sequence through the fault codes at one-second intervals.
If the error is signicant and results in a machine system shutdown, the graphic display will show the
Information Screen until next key switch cycle. Otherwise the Information Screen will be active only when
the Information Switch is pressed.

Fault Code Table

Control System 29Service Manual – SC1500

Display

Code

03 Speed Control fault
04 Scrub Deck Actuator overload The Scrub Deck Actuator has drawn more than 4.5 amps.
08 Solution Solenoid overload

09

10

11 Detergent Pump overload

21 Detergent Pump driver fault

24 Deck Actuator driver fault

30 Solution Solenoid open

32 Scrub Deck Actuator open

35 Brush Contactor (K2) coil open

36

37 Detergent Pump open

52

62 Solution Solenoid driver on

63

64

65 Detergent Pump driver stuck on

70 On-board Battery charger fault

Fault Description Conditions Needed to Set the Fault Code

The E1 Curtis Speed Controller is communicating a problem

to the A1 Control Board.

The Solution Solenoid Valve has drawn more than
approximately 1 amp.

Vacuum Contactor (SSR1) coil
overload

Brush Contactor (K2) coil
overload

Vacuum Contactor (SSR1) coil
open

Scrub Deck Actuator position

fault

Brush Contactor (K2) driver

stuck on

Vacuum Contactor (SSR1) driver

stuck on

The Vacuum Contactor has drawn more than approximately
1 amp.

The Brush Contactor has drawn more than approximately 1
amp.

The Detergent Pump has drawn more than approximately 1
amp.

The driver IC for the Detergent Pump is reporting a fault;
current limiting or shutdown is in effect due to either a
detected over-current or over-temperature condition.

The driver IC for the Deck Actuator is reporting a fault;

current limiting or shutdown is in effect due to either a
detected over-current or over-temperature condition

The measured current was below the minimum value while
the Solution Solenoid should have been on.

The measured current never exceeded the minimum

threshold while moving from one deck position to another

(only valid when the target position and the starting position

switch states should be different).

The measured current was below the minimum value while
the Brush Contactor should have been on.

The measured current was below the minimum value while
the Vacuum Contactor should have been on.

The measured current was below the minimum value while
the Detergent Pump should have been on.

The measured current was greater than or equal to the

minimum threshold value while the deck was moving, but the
software timed out looking for the new position (never saw

the actuator switch states read the target values).

The measured current was above the minimum value while
the Solution Solenoid driver should have been off.

The measured current was above the minimum value while
the Brush Contactor driver should have been off.

The measured current was above the minimum value while
the Vacuum Contactor driver should have been off.

The measured current was above the minimum value while
the Detergent Pump driver should have been off.

An error has been generated via the serial communications
between the charger and the A1 Control Board due to an
incorrect charging prole code being repeatedly sent by the
charger, or the bit timing being severely out of spec.

System Disabled by Fault Codes

Control System 30Service Manual – SC1500

Disable System Flash Indicator

Motor

Display Code

Fault Description

03 Speed Control fault x
04 Scrub Deck Actuator overload x x x x x
08 Solution Solenoid overload x x x
09 Vacuum Contactor (SSR1) coil

overload

10 Brush Contactor (K2) coil

overload
11 Detergent Pump overload x x
21 Detergent Pump driver fault x x
24 Deck Actuator driver fault x x x x
30 Solution Solenoid open x x x
32 Scrub Deck Actuator open x x x x
35 Brush Contactor (K2) coil

open
36 Vacuum Contactor (SSR1) coil

open
37 Detergent Pump open x x
52 Scrub Deck Actuator position

fault
62 Solution Solenoid stuck closed x
63 Brush Contactor (K2) coil

stuck closed

64 Vacuum Contactor (SSR1) coil

stuck closed

65 Detergent Pump stuck closed x
70 On-board Battery charger fault

Disable Detergent

x x x x x x

x x x x x

x x x x x

x x x x x x

x x x x

x x x x x

Disable Solution

Disable Brush

Disable Recovery

Scrub Deck

Vacuum Motor

Actuator Disable

x

Detergent Indicator

Indicator

Brush Motor

Solution Indicator

Vacuum Indicator

Control System 31Service Manual – SC1500

Service Test Mode

The Service Test Mode allows you to switch the individual electrical system components on and off
independent of the normal Operator inputs. This serves as a “shortcut” when troubleshooting the machine
systems.

Note: Once you’ve selected the Service Test Mode from the Hidden Menu,

the only way to exit the Service Test Mode is to press the Scrub On/
Off Switch six times or turn the key switch off.

To Access the Service Test Mode

1. Display the main menu. (Refer to the Programming Options/To Access the Main Menu subsection.)

2. Press the Forward (up) or Reverse (down) Drive Switches to scroll

through the PROGRAMMING OPTIONS menu until the display shows

PROGRAMMING OPTIONS / 16. SERVICE TEST MODE.

3. Press the Burst Of Power Switch to enter the Service Test Mode.

The display will show the Service Test Mode submenu.

PROGRAM OPTIONS

16. SERVICE TEST MODE

SPD: N 26.5 BRU: OFF
REV: OFF VAC: OFF
INH: ON E00 SOL: OFF
DEK: UP CP: OFF

Control System 32Service Manual – SC1500

Service Test Mode Functions

The control panel switches are used to control various A1 Control Board output functions. The table below
lists the control panel switches, and their corresponding Service Test Mode functions and displays:

Control Panel Switch Service Test Mode Function Graphic Display Descriptions

Forward
Drive
Switch

The Forward Drive Switch enables the machine
to drive forward. The blue LED indicator will be

lit when the Switch is active. For the machine

to move forward, the Emergency Stop must be
reset, the Operator Presence Pedal must be
pressed and the Go Pedal must be pressed.
Note that the Inhibit (

INH) output must be off

(via the Information Switch – see below).

SPD: F 26.5 BRU: OFF

REV: OFF VAC: OFF
INH: ON E00 SOL: OFF
DEK: UP CP: OFF

• SPD: – indicates the drive
controller state. In this
case it would display F for
forward.

• The three digits display the
battery voltage (26.5 volts in

this example).

Reverse
Drive
Switch

The Reverse Drive Switch enables the
machine to drive in reverse. The blue LED
indicator will be lit when the Switch is active.
For the machine to move backward, the
Emergency Stop must be reset, the Operator
Presence Pedal must be pressed and the Go
Pedal must be pressed. Note that the Inhibit

(

INH) output must be off (via the Information

Switch – see below).

SPD: R 26.5 BRU: OFF
REV: ON VAC: OFF

INH: ON E00 SOL: OFF
DEK: UP CP: OFF

• SPD: – indicates the drive
controller state. In this
case it would display R for
reverse.

• The three digits display the
battery voltage (26.5 volts in

this example).

• REV: – indicates that the
reverse output is ON.

Information
Switch

Pressing the Information Switch toggles the

Inhibit output (

INH) from the A1 Control Board

to the E1 Curtis Speed Controller ON and OFF.
Note that INH must be OFF in order to test the
forward and reverse drive in the Service Test
Mode.

SPD: R 26.5 BRU: OFF
REV: ON VAC: OFF

INH: ON E00 SOL: OFF

DEK: UP CP: OFF

• INH: – indicates the state

of the inhibit signal. In this

case the inhibit signal is ON.

• E(NN) – displays any active

fault codes.

Extra
Pressure
and Horn
Switches

Pressing the Extra Pressure Switch scrolls
the

DEK: eld through the four available deck

positions:

• UP – raised (transport) position

• VAC – vacuum-only (wet vacuuming) position

• LOW – standard scrub pressure position

SPD: R 26.5 BRU: OFF
REV: ON VAC: OFF
INH: ON E00 SOL: OFF

DEK: UP CP: OFF

DEK: – indicates the scrub

deck position. In this case

the deck would be in the UP

(transport) position.

• HI – extra scrub pressure position

Pressing the Horn Switch will move the deck

to the selected position. Note that the Extra

Pressure Switch is locked out while the deck is

moving. The DEK: line will be highlighted and
inverted.

Control System 33Service Manual – SC1500

Control Panel Switch Service Test Mode Function Graphic Display Descriptions

Scrub
On/Off
Switch

Pressing the Scrub On/Off Switch toggles the
brush motor contactor and scrub deck motor

ON and OFF.

SPD: R 26.5 BRU: OFF
REV: ON VAC: OFF
INH: ON E00 SOL: OFF
DEK: UP CP: OFF

BRU: – indicates the state of

the brush motor. In this case

the motor would be OFF.

Vacuum
Power
Adjustment
Switch

Pressing the Vacuum Power Adjustment Switch
scrolls the Solid State Relay (SSR1) and
Vacuum Motor among the three states:

OFF

(0V), LOW (16.8V) and HI (battery voltage).

SPD: R 26.5 BRU: OFF
REV: ON VAC: OFF
INH: ON E00 SOL: OFF
DEK: UP CP: OFF

VAC: – indicates the state of

the vacuum motor. In this case

the motor would be OFF.

Solution
Flow
Adjustment
Switch

Pressing the Solution Flow Adjustment Switch
toggles the solution solenoid

ON and OFF.

When the solenoid is ON it will operate at 50%
duty cycle (1 cycle = 3 seconds ON, 3 seconds
OFF).

SPD: R 26.5 BRU: OFF
REV: ON VAC: OFF
INH: ON E00 SOL: OFF
DEK: UP CP: OFF

SOL: – indicates the state of

the solution solenoid. In this

case the solenoid would be

OFF.

Detergent
Strength
Switch

Pressing the Detergent Strength Switch toggles
the Detergent Pump

ON and OFF. When the

Detergent Pump is ON, the Pump will be driven
at a rate equivalent to 1:128 (0.8%).

SPD: R 26.5 BRU: OFF
REV: ON VAC: OFF
INH: ON E00 SOL: OFF
DEK: UP CP: OFF

CP: – indicates the state of the

detergent (chemical) pump. In

this case the pump would be

OFF.

To Exit the Service Test Mode

To exit the Service Test mode, press the Scrub On/Off Switch six times or turn the key switch off.

Programming Options

The SC1500 graphic display has two “layers” of hidden menus that allow you to view and change the various
programmable machine congurations, system settings and parameters. The top “layer” is the main menu
from which you can navigate to the 20 submenus. The second “layer” is the submenus that display the
programmable options. These submenus are the screens on which you can change the congurations and
settings.

Control System 34Service Manual – SC1500

To Access the Main Menu

1. Turn the key switch to the Off position. (If the optional on-board battery charger is installed, it must be
unplugged from the AC power).

2. Press and hold in the Solution Flow Adjustment Switch and Extra Pressure
Switch simultaneously.

3. While holding both switches, turn the key switch to the On position.

4. Continue to hold both switches for at least two seconds until the

display shows PROGRAMMING OPTIONS / 1. DECK TYPE in the main

PROGRAM OPTIONS

1. DECK TYPE

menu.

5. Release both switches.

6. Press the Forward (up) or Reverse (down) Drive Switches to scroll through the links in

the main menu.

The main menu contains the following links to the corresponding programming option
submenus:

1. DECK TYPE

2. LOW VOLTAGE CUTOUT

3. BATTERY CHARGER

4. BURST OF POWER

5. DETERGENT OPTION

6. DETERGENT RATE BIAS

7. OPEN FAULT DETECT

8. DISPLAY REV LEVEL

9. LOCKOUT BRUSH

10. LOCKOUT SOLUTION

11. BACKUP ALARM VOL

12. FWD ALARM VOL

13. HORN VOL

14. RESTORE DEFAULTS

15. FAULT RECALL

16. SERVICE TEST MODE

17. XTRA INFO ON DISPLAY

18. FROZEN PARAMETERS

19. PANEL TEST

20. SAVE SCRUB SETTINGS

Service Note: The A1 Control Board will automatically display the main menu upon machine

power-up if no scrub deck has been selected and saved in the DECK TYPE submenu.
This will occur when a new Control Board is installed into a machine, or the

RESTORE DEFAULTS has been performed. The purpose of this is to prompt the

Operator to select the appropriate deck type before using the Control Board in
the machine. Once the deck type has been selected, the controller will no longer
automatically display the main menu at machine power-up.

To Access a Submenu from the Main Menu

1. Press the Forward (up) or Reverse (down) Drive Switches to scroll through the links in
the main menu.

2. To display the selected submenu(s) for the displayed main menu link, press the Burst of
Power Switch.

To Change a Programmable Option in a Submenu

1. Press the Forward (up) or Reverse (down) Drive Switches to scroll through the available
programming options in the submenu(s).

Control System 35Service Manual – SC1500

2. When the desired programming option submenu is displayed, press the Scrub On/Off
Switch. This will enter the displayed programming option and return to the main menu
link.

Deck Type

The SC1500 can be equipped with two different deck options. The 1. DECK

TYPE

submenus allow you to specify the type of deck installed in your
machine. Note that the type of deck selected congures the solution ow
rate settings corresponding to the deck type.

PROGRAM OPTIONS

1. DECK TYPE

PROGRAM OPTIONS
DECK TYPE
20 INCH / 51 CM DISC

PROGRAM OPTIONS
DECK TYPE
20 INCH / 51 CM REV

Low Battery Voltage Cutout

Control System 36Service Manual – SC1500

The purpose of the low battery voltage cutout is to help prolong battery
life. The A1 Control Board will raise the deck, and switch off the brush
and vacuum motors, solution solenoid valve and detergent pump
automatically when the batteries discharge to the selected cutout level.
The 2. LOW VOLT CUTOUT submenus allow you to select the voltage cutout
level for the type of battery installed in your machine:

• The standard cutout setting for wet cell/lead acid batteries is 20.55

volts (80% discharged or 20% charge remaining).

• The alternate cutout setting for gel/maintenance free batteries is 21.75

volts (70% discharged or 30% charge remaining).

The default setting is WET BATTERY 80% / LVC=20.55V.

Battery Charger

The 3. BATTERY CHARGER submenus allow you to specify the battery type
in your machine so the on-board charger will use the charging algorithm
that is compatible with the battery type. If your machine is not equipped
with an onboard charger, select NONE (the default setting).

PROGRAM OPTIONS

2. LOW VOLT CUTOUT

PROGRAM OPTIONS
LOW VOLT CUTOUT
WET BATTERY 80%
LVC=20.55V

PROGRAM OPTIONS
LOW VOLT CUTOUT
MAIN FREE BATTERY 70%
LVC=21.75V

PROGRAM OPTIONS

3. BATTERY CHARGER

PROGRAM OPTIONS
BATTERY CHARGER
NONE

PROGRAM OPTIONS
BATTERY CHARGER
WET 25A

PROGRAM OPTIONS
BATTERY CHARGER
AGM DISCOVER 25A

PROGRAM OPTIONS
BATTERY CHARGER
GEL EXIDE 25A

PROGRAM OPTIONS
BATTERY CHARGER
GEL-AGM 25A

PROGRAM OPTIONS
BATTERY CHARGER
WET 15A

PROGRAM OPTIONS
BATTERY CHARGER
AGM FULLRIVER 25A

Burst Of Power Operation

Control System 37Service Manual – SC1500

The 4. BURST OF POWER submenus allow you to enable or disable the
burst-of-power function. When the burst-of-power function is enabled
(YES), pressing the Burst Of Power Switch while scrubbing will attempt
to make a temporary increase in the solution ow rate, brush pressure,
vacuum level and detergent ow rate.

The default setting is NO.

Detergent (EcoFlex™) Option

The 5. ECOFLEX INSTALLED submenus allow you to enable or disable the
detergent system.

• If the menu setting is YES, the controller will expect a Detergent

Pump to be installed. If no Detergent Pump is installed, eventually the
Control Board could generate an error code.

• If the menu setting is NO, the Detergent Strength Switch has no

effect on machine operation, and the graphic display will not show
the Detergent Indicator Bar Graph. Note that if the machine has a
detergent system installed, it will not work when the menu setting NO
is selected.

PROGRAM OPTIONS

4. BURST OF POWER

PROGRAM OPTIONS
BURST OF POWER
NO

PROGRAM OPTIONS
BURST OF POWER
YES

PROGRAM OPTIONS

5. ECOFLEX INSTALLED

PROGRAM OPTIONS
ECOFLEX INSTALLED
NO

PROGRAM OPTIONS
ECOFLEX INSTALLED
YES

The default setting is NO.

Chemical Rate Bias

The 6. CHEMICAL RATE BIAS submenus allow you to increase or decrease
the detergent/chemical mix rate by 10 percent to achieve a higher or
lower mix concentration than the selected programmed ratio.

• The -10% LESS CHEMICAL

setting will increase

the wait time
between Detergent Pump delivery pulses 10 percent to decrease
detergent ow.

• The +10% MORE CHEMICAL

setting will decrease

the wait time
between Detergent Pump delivery pulses 10 percent to increase
detergent ow.

Note that the 6. CHEMICAL RATE BIAS submenus only have an effect if the

ECOFLEX INSTALLED / YES option is selected (see above).

The default setting is NONE.

PROGRAM OPTIONS

6. CHEMICAL RATE BIAS

PROGRAM OPTIONS
CHEMICAL RATE BIAS
NONE

PROGRAM OPTIONS
CHEMICAL RATE BIAS

-10% LESS CHEMICAL
PROGRAM OPTIONS

CHEMICAL RATE BIAS
+10% MORE CHEMICAL

Open Fault Detect

Control System 38Service Manual – SC1500

Normally, the A1 Control Board will perform checks of the electrical
system during operation. If a fault occurs in a particular system,
that system (and possibly others) will be shut down. This can make
troubleshooting the system difcult. The 7. OPEN FAULT DETECT
submenus allow service personnel to disable all of the open circuit faults
to facilitate troubleshooting. Note that selecting OPEN FAULT DETECT /

OFF

will not disable the over-current protection on any of the systems.

The default setting is OFF.

Display Rev Level

The 8. DISPLAY REV LEVEL submenu displays the revision level of the
software in the A1 Control Board. This revision level is a parameter hard­coded in the software.

PROGRAM OPTIONS

7. OPEN FAULT DETECT

PROGRAM OPTIONS
OPEN FAULT DETECT
OFF

PROGRAM OPTIONS
OPEN FAULT DETECT
ON

PROGRAM OPTIONS

8. DISPLAY REV LEVEL

PROGRAM OPTIONS
DISPLAY REV LEVEL
REV A

Lock Out Brush Pressure

The 9. LOCKOUT BRUSH submenus allow you to lock out the low or high
scrub pressure settings. The Operator will not be able to select a scrub
pressure setting that is locked out.

The default setting is NONE.

PROGRAM OPTIONS

9. LOCKOUT BRUSH

PROGRAM OPTIONS
LOCKOUT BRUSH
NONE

PROGRAM OPTIONS
LOCKOUT BRUSH
LOW

PROGRAM OPTIONS
LOCKOUT BRUSH
HIGH

Lock Out Solution Flow Rate

Control System 39Service Manual – SC1500

The 10. LOCKOUT SOLUTION submenus allow you to lock out single or
multiple solution ow rate settings. The Operator will not be able to
select ow rate(s) that are locked out during normal operation.

The default setting is NONE.

PROGRAM OPTIONS

10. LOCKOUT SOLUTION

PROGRAM OPTIONS
LOCKOUT SOLUTION
NONE

PROGRAM OPTIONS
LOCKOUT SOLUTION
LOW

PROGRAM OPTIONS
LOCKOUT SOLUTION
MEDIUM

PROGRAM OPTIONS
LOCKOUT SOLUTION
HIGH

PROGRAM OPTIONS
LOCKOUT SOLUTION
LOW & MEDIUM

PROGRAM OPTIONS
LOCKOUT SOLUTION
LOW & HIGH

Backup Alarm Volume

The 11. BACKUP ALARM VOL (volume) submenus allow you to set the
backup alarm volume.

The default setting is MEDIUM.

PROGRAM OPTIONS
LOCKOUT SOLUTION
MEDIUM & HIGH

PROGRAM OPTIONS

11. BACKUP ALARM VOL

PROGRAM OPTIONS
BACKUP ALARM VOL
OFF

PROGRAM OPTIONS
BACKUP ALARM VOL
LOW

PROGRAM OPTIONS
BACKUP ALARM VOL
MEDIUM

PROGRAM OPTIONS
BACKUP ALARM VOL
HIGH

Forward Alarm Volume

Control System 40Service Manual – SC1500

The 12. FWD (forward) ALARM VOL (volume) submenus allow you to set
the forward alarm volume.

The default setting is OFF.

Horn Volume

PROGRAM OPTIONS

12. FWD ALARM VOL

PROGRAM OPTIONS
FWD ALARM VOL
OFF

PROGRAM OPTIONS
FWD ALARM VOL
LOW

PROGRAM OPTIONS
FWD ALARM VOL
MEDIUM

PROGRAM OPTIONS
FWD ALARM VOL
HIGH

The HORN VOLUME submenus allow you to set the horn volume.
The default setting is HIGH.

PROGRAM OPTIONS

13. HORN VOLUME

PROGRAM OPTIONS
HORN VOLUME
OFF

PROGRAM OPTIONS
HORN VOLUME
LOW

PROGRAM OPTIONS
HORN VOLUME
MEDIUM

PROGRAM OPTIONS
HORN VOLUME
HIGH

Restore Defaults

Control System 41Service Manual – SC1500

The 14. RESTORE DEFAULTS submenus allow you to reset the programmed
options/parameters stored in the A1 Control Board EEPROM to their
factory default values. Note that selecting RESTORE DEFAULTS / YES will
not reset the hour meter.

The default setting is NO.

Note: IfyouselectYES to restore the defaults, it will be like

installinganew“outofthebox”controller.Therst

time you turn on the key switch, the graphic display will
automatically bring you to the programming options
menu. Also any “user preferences” like brush pressure

lockoutorsolutionowratelockoutwillbelost.

Fault Recall

Whenever the A1 Control Board detects an electrical system fault, one or
more error codes are displayed and stored in the Board EEPROM. The

15. FAULT RECALL submenu allows you to recall any error code(s) that

had been logged from previous machine operation. This can be useful for
troubleshooting the machine.

• Any logged fault codes will be shown on the display. (Fault codes 3, 32
and 52 are shown here in this example.)

PROGRAM OPTIONS

14. RESTORE DEFAULTS

PROGRAM OPTIONS
RESTORE DEFAULTS
NO

PROGRAM OPTIONS
RESTORE DEFAULTS
YES

PROGRAM OPTIONS

15. FAULT RECALL

PROGRAM OPTIONS
FAULT RECALL
3 32 52

• If no fault code is present, the display will show a “-“

Pressing the Burst Of Power Switch with the FAULT RECALL submenu

PROGRAM OPTIONS
FAULT RECALL

-

displayed will erase the fault history and the entire Frozen Parameters
memory. (Refer to the Frozen Parameters subsection.)

Note that there may be a slight delay after pressing the Burst Of Power Switch before the “-“ symbol
appears to conrm that the memory has been cleared. This is normal and is due to the large amount of
Frozen Parameter data that is being erased.

Service Test Mode

Pressing the Burst Of Power Switch with the 16. SERVICE TEST MODE
main menu link displayed will put the machine into the Service Test

PROGRAM OPTIONS

16. SERVICE TEST MODE

Mode and display the Service Test Mode submenu.

Refer to the Troubleshooting/Service Test Mode subsection for
information regarding the Service Test Mode functions.

SPD: N 26.5 BRU: OFF
REV: OFF VAC: OFF
INH: ON E00 SOL: OFF
DEK: UP CP: OFF

Extra Information on the Graphic Display

Control System 42Service Manual – SC1500

The 17. EXTRA INFO ON LCD submenus allow you to display additional
information on the graphic display. This additional information is
displayed in real time on both the Scrubbing and Information screens and
can aid in troubleshooting the machine in normal operation.

The extra information is displayed in a two-letter or three-letter code that
identies the information. A number below the letter code indicates the
unit value in amps or volts.

Only one type of extra information can be displayed at any time, but the
selected information can be changed at will via the 17. EXTRA INFO ON

LCD

submenus. Descriptions of the letter codes are as follows:

• BV = Battery Voltage

• LOK = Battery Lock Level

• ACT = Deck Actuator Current

• SOL = Solution Solenoid Current

• BRU = Brush Motor Contactor Current

• VAC = Vacuum Motor Contactor Current

• DET = Detergent/Chemical Pump Current

The default setting is NONE.

PROGRAM OPTIONS

17. EXTRA INFO ON LCD

PROGRAM OPTIONS
EXTRA INFO ON LCD
NONE

PROGRAM OPTIONS
EXTRA INFO ON LCD
BATT VOLTS

PROGRAM OPTIONS
EXTRA INFO ON LCD
BATT LOCK VALUE

PROGRAM OPTIONS
EXTRA INFO ON LCD
ACTUATOR CURR

PROGRAM OPTIONS
EXTRA INFO ON LCD
SOLUTION CURR

PROGRAM OPTIONS
EXTRA INFO ON LCD
BRUSH CONT CURR

PROGRAM OPTIONS
EXTRA INFO ON LCD
VAC CONT CURR

PROGRAM OPTIONS
EXTRA INFO ON LCD
CHEM PUMP CURR

Frozen Parameters

Control System 43Service Manual – SC1500

The 18. FROZEN PARAMETER rst and second-level submenus allow you
to view the machine parameters that were saved prior to when an error
code was detected. This can be helpful when troubleshooting intermittent
problems that are causing a code to set.

Note: Frozenparametersareonlysavedfortherstcodethatis

set, not for any subsequent codes.

Eleven different machine parameters are logged, and all but the error
code number and hour meter time are saved at 0.1 second intervals for
the 12.8 seconds leading up to the time of the error code. This results in a
total of 128 data points (one every 0.1 seconds) for each parameter. These
data points are displayed in a second-level of submenus.

The rst-level ERROR CODE submenu displays the error code number (32
in this example). The rst-level HOUR METER submenu displays the time
on the hour meter when the error code occurred (12:15 in this example).
The other nine rst-level submenus are links to the next (second) layer of
submenus that display the 128 data points corresponding to the functions
listed on the submenus.

Note that in the second-level submenus, data point #1 is the newest value
and #128 is the oldest value (that occurred 12.7 seconds earlier).

Pressing the Forward (up) or Reverse (down) Drive Switches will scroll
through the 18. FROZEN PARAMETER rst-level submenus shown here.

PROGRAM OPTIONS

18. FROZEN PARAMETER

PROGRAM OPTIONS
FROZEN PARAMETER
ERROR CODE
32

PROGRAM OPTIONS
FROZEN PARAMETER
HOUR METER
12:15

PROGRAM OPTIONS
FROZEN PARAMETER

3. BATT VOLTAGE
PROGRAM OPTIONS

FROZEN PARAMETER

4. ACTUA TOR CURR
PROGRAM OPTIONS

FROZEN PARAMETER

5. SOLUTION CURR
PROGRAM OPTIONS

FROZEN PARAMETER

6. VAC CONT CURR
PROGRAM OPTIONS

FROZEN PARAMETER

7. BRU CONT CURR
PROGRAM OPTIONS

FROZEN PARAMETER

8. DET PUMP CURR
PROGRAM OPTIONS

FROZEN PARAMETER

9. DIRECTION
PROGRAM OPTIONS

FROZEN PARAMETER

10. ACT SW 1
PROGRAM OPTIONS

FROZEN PARAMETER

11. ACT SW 2

To display the parameter data points in a second-level submenu:

Control System 44Service Manual – SC1500

1. Press the Forward (up) or Reverse (down) Drive Switch to scroll

through the available rst-level submenus. (The rst-level submenu

3. BATT VOLTAGE is selected in this example.)

2. Press the Burst of Power Switch to display the second-level submenu.

(The second-level submenu 3. BATT VOLTAGE / 1: 20.35 is shown in this
example.) This submenu tells you that at data point 1 (0.1 seconds

PROGRAM OPTIONS
FROZEN PARAMETER

3. BATT VOLTAGE

FROZEN PARAMETER

3. BATT VOLTAGE
1: 20.35

prior to the error code), the battery voltage was 20.35 volts.

Note that if the selected rst-level submenu has no second-level submenu, the Burst of Power Switch
will have no effect.

3. To go back one level from a second-level submenu to a rst-level submenu, press the Scrub On/Off

Switch.

To scroll through the data points on a second-level submenu:

When you display a rst-level submenu, the Detergent On/Off Indicator (LED) will turn on.

When you display a second-level submenu, pressing the Detergent Strength Switch will
toggle the data point scrolling mode between the fast and slow scrolling modes. The two
scrolling modes work as follows:

• In the slow scrolling mode the
increment/decrement value is 1 (0.1
seconds). Pressing the Forward Drive

FROZEN PARAMETER

3. BATT VOLTAGE
1: 20.35

FROZEN PARAMETER

3. BATT VOLTAGE
126: 20.45

Switch will step you from data record
1 to 2, 2 to 3, etc. Pressing the Reverse
Drive Switch will step you from data
record 128 to 127, 127 to 126, etc.

FROZEN PARAMETER

3. BATT VOLTAGE
2: 20.36

FROZEN PARAMETER

3. BATT VOLTAGE
127: 20.47

• In the fast scrolling mode the
increment/decrement value is 10 (one
second). Pressing the Forward Drive
Switch will step you from data record
10 to 20, 20 to 30 etc. Pressing the
Reverse Drive Switch will step you
from data record 120 to 110, 110 to
100, etc.

The purpose of the fast-scrolling feature
is to reduce the number of switch presses
required to cycle through all 128 data
points if you choose to do so.

FROZEN PARAMETER

3. BATT VOLTAGE
3: 20.37

FROZEN PARAMETER

3. BATT VOLTAGE
10: 24.53

FROZEN PARAMETER

3. BATT VOLTAGE
20: 24.59

FROZEN PARAMETER

3. BATT VOLTAGE
30: 24.52

FROZEN PARAMETER

3. BATT VOLTAGE
128: 20.55

FROZEN PARAMETER

3. BATT VOLTAGE
100: 24.57

FROZEN PARAMETER

3. BATT VOLTAGE
110: 24.54

FROZEN PARAMETER

3. BATT VOLTAGE
120: 24.56

Control System 45Service Manual – SC1500

This fast-scrolling feature will automatically end when you press the Scrub On/Off Switch to leave a second­level submenu.

The Detergent On/Off Indicator will turn off when you press the Scrub On/Off Switch again to leave the rst­level submenu.

To capture the parameters prior to another fault condition, you’ll need to clear the current fault from the 15.

FAULT RECALL

submenu. (Refer to the Fault Recall subsection.)

Panel Test

The 19. PANEL TEST submenus allow you to verify the function of the control panel membrane switches and
LEDs, This will help identify any intermittent or non-functioning switches or LEDs.

When you display the PROGRAM OPTIONS / 19. PANEL TEST main menu
link and press the Burst of Power Switch, all LEDs will turn off.

When you press a membrane switch, the display will show the name of
the switch on the line below PANEL TEST. The display shows that the

HORN Switch has been pressed one time in this example.

PROGRAM OPTIONS

19. PANEL TEST

PROGRAM OPTIONS
PANEL TEST
HORN
1

With the exception of the Horn and Information Switches, which have no
LED indicator associated with them, the switch LED indicators will light when the corresponding membrane
switch is pressed. Note that the Vacuum Power Adjustment and Burst Of Power Switches each have two
LED indicators associated with them.

The following table lists the control panel membrane switches and the
LED indicators that will light when the switch is pressed:

Membrane Switch

LED Indicator That Will Light When the

Switch is Pressed

Horn Switch Amber LED on the

Burst Of Power Switch.

Information
Switch

Vacuum Power
Adjustment
Switch

Burst of Power
Switch

Quiet Vacuum Mode
Indicator on the Vacuum
Power Adjustment
Switch

Standard Vacuum
Mode Indicator on the
Vacuum Power
Adjustment Switch

Green Burst of Power
Indicator on the Burst
of Power Switch

Control System 46Service Manual – SC1500

Membrane Switch

Scrub On/Off

LED Indicator That Will Light When the

Switch is Pressed

Scrub On/Off Indicator

Switch

Extra Pressure

Extra Pressure Indicator

Switch

Solution Flow

Solution On/Off Indicator
Adjustment
Switch

Detergent
Strength

Detergent On/Off

Indicator
Switch

Note that the switch name display and LED indicator will stay on until a different membrane switch is
pressed.

Each switch has its own switch counter. When you press a switch, the
corresponding counter will be displayed on the bottom line of the graphic

PROGRAM OPTIONS

19. PANEL TEST

display. Each switch press will increment the counter one digit until it
hits 255, after which the counter will roll over to 0. The

HORN

Switch is shown in this example.

Press the Scrub On/Off Switch six times to exit the 19. PANEL TEST main
menu link.

PANEL TEST /

PROGRAM OPTIONS
PANEL TEST
HORN
1

PROGRAM OPTIONS
PANEL TEST
HORN
255

PROGRAM OPTIONS
PANEL TEST
HORN
0

Save Scrub Settings

Control System 47Service Manual – SC1500

The 20. SAVE SCRUB SETTINGS submenus allow you determine whether
the machine uses the scrub settings that were in use when the key switch
was switched off, or the default settings.

Removal and Installation

A1 Control Board

Caution! Electronic devices like the A1 Control Board are sensitive to Electrostatic Discharge

(ESD). Before handling the Control Board, touch a metal bench or shelf to discharge
any electrical charge that may have built up in your body. Do not walk around with a
Control Board in your hands.

1. Disconnect the
batteries.

2. Remove the four

Phillips Screws and
Flat Washers holding

the Interface Panel

Assembly
Control Panel.

to the

Phillips Screw

and Flat

Washer (4)

Control

Panel

PROGRAM OPTIONS

20. SAVE SCRUB SETTINGS

PROGRAM OPTIONS
SAVE SCRUB SETTINGS
YES

PROGRAM OPTIONS
SAVE SCRUB SETTINGS
NO

Interface

Panel

Assembly

3. Carefully lift the

Interface Panel
Assembly
Control Panel.

out of the

Control System 48Service Manual – SC1500

4. Carefully disconnect the Electrical

Connectors

from the A1 Control Board.

5. Remove the Phillips Screws and

grounding strap, then remove the A1

Control Board
Assembly

from the Interface Panel

.

6. Reinstall the A1 Control Board by

following the above steps in reverse
order.

Interface Panel

Assembly

Control

Panel

Electrical

Connector

(typical)

A1

Control

Board

Phillips

Screw

(typical

Interface

Panel

Assembly

E1 Curtis 1210 Speed Controller

1. Disconnect the
batteries.

2. Remove the four

Phillips Screws and
Flat Washers holding

the Interface Panel

Assembly
Control Panel.

to the

Phillips Screw

and Flat

Washer (4)

Control

Panel

Control System 49Service Manual – SC1500

Interface

Panel

Assembly

3. Carefully lift the

Interface Panel
Assembly
Control Panel.

out of the

Interface Panel

Assembly

Control

Panel

4. Carefully disconnect
the Electrical

Connectors
E1 Curtis 1210 Speed

Controller

from the

.

5. Remove the two Socket

Head Screws

and

remove the E1 Curtis

1210 Speed Controller

from the Control Panel.

6. Reinstall the E1 Curtis

1210 Speed Controller

by following the above
steps in reverse order.

Control System 50Service Manual – SC1500

Electrical

Connector

(typical)

E1 Curtis

1210 Speed

Controller

Socket Head

Screw (2)

Control

Panel

Control System 51Service Manual – SC1500

A1 Control Board Shop Measurements

The following table lists measurements taken from one SC1500. While these are not “specications”, they
can help you recognize abnormal vs. normal conditions.

Note that the black voltmeter lead is on B- unless otherwise indicated.

Pin Color Description Ref. Measurements

J1-1 RED/YEL Chemical Pump

+
J1-2 ­J1-3 BLU/GRY Chemical Pump B- 2.1v not on
J1-4 ­J1-5 ­J1-6 ­J1-7 RED/YEL Inhibit SPC B- 0.001v no direction selected

J1-8 BLK B- 0.09v Vacuum on
J1-9 BLU Brush Act. - B- 2.1v or 3.8v at rest

B- 2.1v not on

23.2v FWD or REV requested

0.2v extending

22.9v retracting

J1-10 ORN/BLK Brush Act. + B- 2.1v or 3.8v at rest

0.2v retracting

22.9v extending
J2-1 BLK B- B- 0.09v Vacuum On
J2-2 BLK B- B- 0.09v Vacuum On
J2-3 ORN Batt. Chg.

Comm.

J2-4 ­J2-5 ­J2-6 ­J2-7 BLK B- B- 0.09v Vacuum On
J2-8 BLK B- B- 0.09v Vacuum On
J2-9 -

J2-10 -

J2-11 BLK/WHT Act. Position 2 B- 4.99v switch open

J2-12 RED/VIO Act. Position 1 B- 4.99v switch open

B- 0.8v key off

Plug in Charger: 12v, then 3.9v, then 12 v

0.03v switch closed

0.03v switch closed
J3-1 BRN/VIO B+ B- 24.5v key off or on
J3-2 ­J3-3 RED/BRN Reverse B- 0v no direction request or forward request

23.1v reverse direction request

Pin Color Description Ref. Measurements

J3-4 BRN Dead Man

Switch

J3-5 BLU/BLK Rev . Alarm B- 23.4v forward or stationary

J3-6 RED/WHT Motion B- 24v stationary

J3-7 ORN/BLU Status B- 1.77v when no code

J3-8 BRN B+ B- 24.4v key off or on
J3-9 GRN/BLK Horn - B- 14.9v horn off

J3-10 ORN/RED Horn + B- 14.9v horn off or on

J3-11 VIO/BLK Solution

Solenoid

J3-12 GRA/BLK Vacuum Control B- 23.4v Vacuum off

B- 24.4v when pressed (Key and Emergency

Switch also closed)

1.5v in reverse

0.1v moving forward or reverse

Unstable when code – max 23.5v

0.004v horn on

B- 24.4v solenoid off

0.12v solenoid on

Control System 52Service Manual – SC1500

6.9v Vacuum low

0.104 Vacuum high

J3-13 WHT/RED Brush

Contacator

J3-14 BRN Key Switch B- 0v key off

B- 24.3v off

0.2v on

24.2v key on

Electrical System

Functional Description

Overview

The electrical system consists of the switches, circuit breakers and contactors mounted on and underneath
the control panel assembly, the 150-amp main fuse, on-board battery charger (if so equipped) and the
batteries.

The electrical system is powered by two 12-volt or four 6-volt batteries for a total of 24 volts. Heavy cables
connect the batteries in series. On machines without an on-board battery charger, a large red main battery
pack connector is used for connecting the batteries to a “shelf” battery charger unit.

The control system will turn off the scrub system and recovery systems if the battery voltage drops too low to
prevent damage to the batteries due to excessive discharging.

The circuit breakers and a 150-amp fuse protect various circuits from excessive current.

The machine wiring is color coded, and the wires are
marked corresponding to their location on the Wiring

Harness Diagram. (Wire W010 to the Brush Contactor K2

is shown in this example.)

53Service Manual – Advance SC1500

On-board Battery Charger

The optional on-board battery charger is mounted on the
bottom of the machine. The charger has an internal relay
that interrupts power to the machine when the charger
is plugged into an AC power outlet. This prevents the
machine from being operated while the batteries are
charging. Wiring changes must be made when installing
the battery charger for the interlock circuit to work
correctly.

Here is how the battery charger interlock circuit works. The interlock relay contacts inside the charger are
normally closed, allowing the current to pass in and out of the charger to the A1 Control Board and the
Speed Controller. When the AC power cord is plugged in, the relay is energized and opens the relay contacts
opening the circuit.

When the battery charger is plugged in, the graphic display will
show the battery type, and a battery icon with 0 to 5 bars to show
the charging progress.

The battery charger and A1 Control Board communicate with one
another on the YEL/ORN wire that runs between them. Each time the battery charger is plugged in, the
charger contacts the Controller by sending out a positive voltage on the communication wire to nd out what
kind of batteries are in the machine. It needs to know this in order to use the correct charging prole. The
Controller responds and provides the battery type information it has stored in memory. The charger then
tells the Controller which charging prole it will use and begins charging the batteries.

Refer to the Control System/Programming Options section for information on how to tell the controller what
kind of batteries are used in the machine. If the charger is unable to communicate with the controller it will
use the prole for a wet battery at a 25-amp rate as a default.

Battery Charger Circuit Descriptions

Battery Charger Not Plugged In

Electrical System 54Service Manual – SC1500

F1

RED

AB

B+

Gnd

12

YEL/ORN

CB2

RED BRN/VIO WHT/BRN BLU BLK

Circuit Breaker, 5 Amp

11 1

S1

Switch

Switch J3-4

22 22

Dead Man

SPST Key

Fuse, 150 A.

12

B-

Internal Relay
in Battery Charger

3

Emergency
Stop
S4

1

RED

BLK

Dead Man Switch

S2

X161C X162C

BRN

BT1

Battery 12 VDC

+

A1

Control Board

YEL/ORN

Main Machine

Controller

J2-3 Bat Charger
On-board Communication

E1

Curtis 1210

Speed

Controller

-

Pin 5 - KSI

When the Battery Charger is not plugged in, the Internal Relay in the charger is de-energized and the
contacts on the Internal Relay are closed. This allows power from the Key Switch to enter terminal 2 on the

Internal Relay, pass through the closed contacts, then exit terminal 1. This provides power to Pin J3-4 on

the A1 Control Board and Pin 5 (key switch input) on the E1 Curtis Speed Controller to allow normal machine
operation.

Battery Charger Plugged In

Electrical System 55Service Manual – SC1500

F1

RED

AB

B+

Gnd

12

YEL/ORN

CB2

RED BRN/VIO WHT/BRN BLU BLK

Circuit Breaker, 5 Amp

11 1

S1

Switch

Switch J3-4

22 22

Dead Man

SPST Key

Fuse, 150 A.

12

B-

Internal Relay
in Battery Charger

3

Emergency
Stop
S4

1

RED

BLK

Dead Man Switch

S2

X161C X162C

BRN

BT1

Battery 12 VDC

+

A1

Control Board

YEL/ORN

Main Machine

Controller

J2-3 Bat Charger
On-board Communication

E1

Curtis 1210

Speed

Controller

-

Pin 5 - KSI

When the Battery Charger is plugged in, the Internal Relay in the charger is energized and the contacts on the

Internal Relay open. This prevents the power from the Key Switch from reaching the A1 Control Board and E1
Curtis Speed Controller

to disable all cleaning and driving functions while the Battery Charger is plugged in.

Note that terminal 3 on the Internal Relay is the communication line (YEL/ORN wire) between the Battery

Charger

and the A1 Control Board.

Component Locations

The following electrical components are included in this section:

• Batteries • Optional On-board battery charger

• Switches • Circuit Breakers

• Contactors/Relays • 150-amp Fuse

The Batteries sit in the

Battery Tray. To access

the Batteries, lift up the

Control Panel Housing

/ Recovery Tank Cover

,

engage the Prop Rod,
then tilt the Recovery

Tank

back.

Control Panel

Housing/

Recovery

Tank Cover

Prop Rod

Batteries

Electrical System 56Service Manual – SC1500

Recovery

Tank

Battery

Tray

The On-board Battery Charger is mounted
on the underside of the machine above the
scrub deck.

On-board

Battery

Charger

The 25-amp Circuit Breaker
(CB4), 20-amp Circuit

Breaker
Breaker
Circuit Breaker

Speed Control Potentiometer

(CB3), 5-amp Circuit
(CB2) and 50-amp

(CB1), 100k

(R1), Emergency Disconnect
and Key Switch (S1) are all
mounted on the back of the

Control Panel.

100k Speed

Control

Potentiometer

Control

Panel

25-amp

Circuit

Breaker

20-amp

Circuit

Breaker

5-amp

Circuit

Breaker

Electrical System 57Service Manual – SC1500

50-amp

Circuit

Breaker

Emergency
Disconnect

Key

Switch

The Solid State Relay/

Vacuum Motor Power Module

(K1), Brush Contactor (K2)
and 150-amp Fuse are
located inside the control
panel assembly.

Solid State

Relay/Vacuum Motor

Power Module

150-amp

Fuse

Brush Motor

Contactor (K2)

Electrical Diagrams

RELEASE, REV A MODIFIED

UNDERSTANDING THAT IT WILL NOT BE REPRO-

N FOR WHICH IT WAS ISSUED AND RECIPIENT

THIS DRAWING AND THE DESIGN REPRESENTED HEREON IS THE PROPERTY OF NILFISK-ADVANCE, INC.,

CONFIDENTIAL

PLYMOUTH, MINNESOTA 55447-3408

NILFISK-ADVANCE, INC.

PMO HH

PMO HH
UPDATE: A1(CONTROL BOARD) MAIN MACHINE
CONTROLLER WAS CONTROL BOARD, R2 WAS

SOLID STATE "RELAY" WAS SSR1, VACUUM

POWER MODULE WAS VACUUM, DETERGENT
PUMP WAS CHEMICAL PUMP, CHARGER SYMBOL
ADD: NOTE 2, SYMBOL AND NOTE, CONNECTORS
X143 A-B, X144 A-B, X157 A-B, X158 A-B, X161 A-F

REVISED/REDISIGNED: MOTOR BRUSH LIFT

REMOVED: MOTOR BRUSH BOOST

Note: Refer to the individual machine system sections for the system ladder diagrams and circuit

descriptions.

Wiring Diagram, p/n 56104081, Rev. B, Page 1

F1

FUSE, 150A.

CB1

RED

WHEN CHARGER IS NOT UNSTALLED
THERE NEEDS TO BE A JUMPER BETWEEN
PINS 1 AND 2 ON CONNECTOR X126
ON MAIN HARNESS

CIRCUIT BREAKER, 5 AMP

RED

12

CIRCUIT BREAKER, 50A.

B

123

YEL/ORN

CB2

12

SW, SPST KEY

BRN/VIO

BRN

S1

1 2

BRN/VIO

RED

GND

~

123

1 2

AB

B+ B-

E2
CHARGER S.P.E. (OPTIONAL)

B

EMERGENCY STOP

S4

1 2

J3-1 B+
J3-8 B+

J3-14 KEY SWITCH

RED

BLK

DEADMAN SWITCH

B

B

S2

WHT/BRN BLK

X161C

X162C

DEAD MAN
SWITCH J3-4

21

BRN

BT1

BATTERY, 24 Vdc

+ -

B

X162E

X161E

B

1 2

Y1
BRAKE

BB

X162D

ORN

BLK

X144A

X161D

B

BRN/BLK

X158A

B

PLYMOUTH, MINNESOTA AND IT HAS BEEN ISSUED WITH THE
DUCED NOR COPIED NOR USED FOR ANY PURPOSE OTHER THA
AGREES TO RETURN IT UPON REQUEST.

DWG. NO. SHEET

56104081

BRNBLU

ORN

1 OF 2

Electrical System 58Service Manual – SC1500

REV ECO DATE DFTM APPD

A

R1,

MOTOR

B

X162 A-F,

ACTUACTOR

REVISIONS

A-07411 10-19-11

A-09223 4-2-13

B

2

K2

BRN

RED

BRN

YEL/ORN

B+

WHT/RED

CONTACTOR, BRUSH

L1

1 2

VIO/BLK

VALVE, SOLENOID

H1

- +

ORN/RED

HORN

GRN/BLK

M2

+-

M

OPTIONAL

DETERGENT PUMP

BLU/GRY

RED/YEL

B

A1 (CONTROL BOARD)
MAIN MACHINE CONTROLLER

J3-13 BRUSH
CONTACTOR

J3-11 SOLUTION
SOLENOID

J3-10 HORN +

J3-9 HORN -

J1-1 + DETERGENT
PUMP

J1-3 - DETERGENT
PUMP

MOTION J3-6

STATUS J3-7

REV. ALARM J3-5

B

B

B- J2-8
B- J2-7
B- J2-1
B- J2-2

RED/WHT

100K POT

YEL

BB B B

BLK

X162B

X161B

X144B

X158B

RED/YEL

ORN/BLU

RED/BRN

1

B

2

GRN/ORG

R1

3

S5

21

BLU

X162A

GO SWITCH

NOTES UNLESS OTHERWISE

1. ALL DIMENSIONS IN INCHES.

2. DO NOT SCALE DRAWING.

3. ALL DIMENSIONS APPLY AFTER
PLATING AND HEAT TREATING,

RED/WHT

YEL

VIO

SPECIFIED

E1
CURTIS 1210 SPEED

B

CONTROLLER

B

RED/WHT

X161A

BLK
BLK
BLK
BLK

GRA

PIN 6 - BRAKE -

PIN 12 - INHIBITINHIBIT SPC J1-7

PIN 9 - STATUS

PIN 16 - REV. ALARM

PIN 17 - DRIVE SWITCH

PIN 3 - HIGH

PIN 18 - SPEED LIMIT

PIN 13 - POT. LOW

PIN 4 - GO SWITCH

DRAWN

10-19-11

CHECKED

PROJ ENG

10-19-11

B+

PIN 5 - KSI

PIN 14 - BRAKE +

B-

YEL/BLK

M1

RED/GRN

M2

B-

PMO

HH

X143B

X143A

BLKBLU/BLK

BB

X157B

BB

X157A

YEL/BLK

M1

RED/GRN

2

M

1

MOTOR, WHEEL DRIVE

Wiring Diagram, p/n 56104081, Rev. B, Page 2

REVISIONS

REV ECO DATE DFTM APPD

SEE SHEET 1

PLYMOUTH, MINNESOTA AND IT HAS BEEN ISSUED WITH THE UNDERSTANDING THAT IT WILL NOT BE REPRO-
DUCED NOR COPIED NOR USED FOR ANY PURPOSE OTHER THAN FOR WHICH IT WAS ISSUED AND RECIPIENT

THIS DRAWING AND THE DESIGN REPRESENTED HEREON IS THE PROPERTY OF NILFISK-ADVANCE, INC.,

CONFIDENTIAL

RED

B+

YEL/ORN

CIRCUIT BREAKER, 20 AMP

CB3

12

BLU/ORN WHT

VACUUM MOTOR POWER MODULE

4-

3+

K1

SOLID STATE "RELAY"

1-

2+

D2

GRA/BLKBRN

B

B

J2-3 BAT CHARGER
ON BOARD COMMUNICATION

BRUSH ACT (-) J1-9

A1(CONTROL BOARD)
MAIN MACHINE CONTROLLER

ACT POSITION1 J2-12

ACT POSITION2 J2-11

J3-12 VACUUM MOTOR
POWER MODULE

BRUSH ACT (+) J1-10

B

B- J1-8

MOTOR, BRUSH LIFT ACTUACTOR

A

D

C

F

B

BLU

YEL/BLK

RED/VIO

POS 2

BLK/WHT

ORN/BLK

TOP LIMIT

POS 1

2 1

2 1

BOTTOM LIMIT

1 2

M4

2 1

2 1

M

MOTOR, VAC

DWG. NO. SHEET

B

-

M3

M

+

Electrical System 59Service Manual – SC1500

AGREES TO RETURN IT UPON REQUEST.

56104081

2 OF 2

B

B-

BLK

CIRCUIT BREAKER, 25 AMP

CB4

12

BRN/VIO

K2

4 3

CONTACTOR, BRUSH

M5

RED BLK

+-

M

MOTOR, BRUSH

Wiring Harness Diagram, p/n 56104082, Rev. B

Electrical System 60Service Manual – SC1500

Electrical System 61Service Manual – SC1500

Electrical Connector Pin-out Assignments

The following tables list the individual connector pin-out assignments. The tables include connector
illustrations to help you identify the various connectors on the machine. The connector pin-out information is
organized by connector ID in alphabetical order.

To Locate and Identify a Connector

For example, if you need to nd out which connector is on the L1 (solution) Solenoid Valve and what it looks
like, refer to the Wiring Harness Diagram. The Wiring Harness Diagram shows that connector X7 is on
the L1 (solution) Solenoid Valve. Refer to the Wiring Diagram and the appropriate table below, X7 (Delphi

12015792)

in this example, for the corresponding wire colors, and wire and connector pin assignments.

Section of Wiring
Harness Diagram

X7 (Delphi 12015792)

Pin# Conductor Wire Color

A W284 BRN
B W283 VIO/BLK

Section of Wiring Diagram

Connector Pin-out Assignment Tables

J1 (Molex Mini Fit Jr. 39012105)

Pin# Conductor Wire Color

1 W279 RED/YEL
2 – –
3 W280 BLU/GRA
4 – –
5 – –
6
7 W302 RED/YEL

YEL/BLK

8 W165

Electrical System 62Service Manual – SC1500

9 W054 BLU

10 W055 ORN/BLK

J2 (Molex Mini Fit Jr. 39012125)

Pin# Conductor Wire Color

1 W162 BLK
2 W161 BLK
3 W174 YEL/ORN
4 – –
5 – –
6 – –
7 W163 BLK
8 W164 BLK
9 – –

10 – –

11 W218 BLK/WHT

12 W204 RED/VIO

J3 (Molex Mini Fit Jr. 39012145)

Pin# Conductor Wire Color

1 W181 BRN/VIO
2 – –
3 W166 RED/BRN
4 W294 BRN
5 W066 BLU/BLK
6 W277 RED/WHT
7 W067 ORN/BLU
8 W182 BRN/VIO
9 W281 GRN/BLK

10 W282 ORN/RED

11 W283 VIO/BLK
12 W003 GRA/BLK
13 W010 WHT/RED
14 W183 BRN

Electrical System 63Service Manual – SC1500

J4 (39012185)

Pin# Conductor Wire Color

1 – –
2 – –
3 W060 YEL
4 W272 GRA
5 W293 BRN
6 W276 RED/WHT
7 – –
8 – –
9 W067 ORN/BLU

10 – –

11 – –
12 W302 RED/YEL
13 W064 VIO
14 W278 ORN
15 – –
16 W066 BLU/BLK
17 W166 RED/BRN
18 W217 GRN/ORN

Electrical System 64Service Manual – SC1500

X2 (Ducon 12147067)

Pin# Conductor Wire Color

A W199 BLK

B W167 RED

X6 (Delphi 12052613)

Pin# Conductor Wire Color

A W191 WHT

B W194 BLK

X7 (Delphi 12015792)

Electrical System 65Service Manual – SC1500

Pin# Conductor Wire Color

A W284 BRN

B W283 VIO/BLK

X126 (AMP 282087-1)

Pin# Conductor Wire Color

1 W172 BRN
2 W173 RED-VIO
3 W174 YEL-ORN

X127 (Delphi 15363990)

Pin# Conductor Wire Color

A W170 RED

B W171 BLK

X139 (Delphi 12020786)

Electrical System 66Service Manual – SC1500

Pin# Conductor Wire Color

A W055 ORN/BLK
B W054 BLU
C W204 RED/VIO
D W165 YEL/BLK
E – –

F W218 BLK/WHT

X143 (Ducon 12147067)

Pin# Conductor Wire Color

A W273 RED/GRN
B W274 YEL/BLK

X144 (Delphi 12015792)

Pin# Conductor Wire Color

A W278 ORN
B W275 RED/WHT

X161 (Delphi 12020926)

Electrical System 67Service Manual – SC1500

Pin# Conductor Wire Color

A W272 GRA
B W271 YEL
C W289 WHT/BRN
D W293 BRN
E W294 BRN

Troubleshooting

Note: Refer to the individual machine system sections for electrical troubleshooting procedures.

Problem Cause Correction

No power to the
machine.

Insufcient machine

run time.

The battery charger

does not charge.

Discharged batteries. Check the battery voltage and charge as necessary.

Poor battery connection(s). Check the battery cables, terminals and connections

and tighten/repair/replace as necessary.

Batteries need to be

replaced.
Incorrect low-voltage cutout

setting.

Batteries not fully charged. If there is any question whether the batteries are

One or more weak batteries.

Poor battery connection(s). Check the battery cables, terminals and connections

Battery charger not
operating correctly.

There’s a problem with

the charger wiring and/or
connections.

One or more weak batteries Check and replace the batteries as necessary.

Perform a load test on the batteries and replace if

necessary.

Make sure the low battery voltage cutout setting is
correct for the battery type in the machine. (Refer

to the Control System/Programming Options/Low

Battery Voltage Cutout subsection.)

fully charged, they should be charged for at least 16

hours.

• Measure the voltage across each individual

battery while operating the machine. Write down
the values and compare them. A battery that has a
dead cell will typically be 1 - 2 volts lower than the

others.

• Use a battery load tester to test each battery.

• For wet batteries, a hydrometer can be used to
check the specic gravity of the electrolyte in each

cell. A dead cell is one that reads 50 points or
more lower than the other cells.

and tighten/repair/replace as necessary.

1. Check the charger 120VAC power cord and
power source to the charger and repair as
necessary.

2. If the electrical connections are OK, replace the
charger.

Check the charger connections to the machine and

repair as necessary.

Electrical System 68Service Manual – SC1500

Note:

The optional on-board battery charger will charge, even if it cannot communicate with the

A1 Control Board.

Specications

Component Specications

Batteries (4) Six-volt, 260 amp-hour, 20-hr. Rate

Input – 100-240 VAC, 50/60Hz

Battery Charger

Output – 24V, 25A

Electrical System 69Service Manual – SC1500

Solid State Relay/Vacuum
Motor Power Module (K1)

Brush Contactor (K2) Nominal Coil Resistance – 58.3 ohms ±10%

Operating Voltage – 7-48 VDC
Rated Load Current – 40A

Recovery System

Functional Description

The Recovery System pulls the wastewater from the squeegee and directs it into the recovery tank. The
24-volt, three-stage electric vacuum motor creates a vacuum in the recovery tank with sufcient airow to
lift the used cleaning solution from the squeegee and into the vacuum hose assembly, which then directs the
water into the recovery tank.

The Operator can select from two vacuum power levels – standard and quiet vacuum.
The Recovery System includes the Vacuum

Hose Assembly
Vacuum Motor, Solid State Vacuum Relay, Float
Cage Assembly

• The Vacuum Hose Assembly attaches to

the squeegee assembly and directs the
wastewater from the squeegee to the Debris

Cage

and Recovery Tank.

• The Vacuum Motor creates a vacuum inside

of the Recovery Tank to pull the wastewater
from the squeegee into the Recovery Tank.

• The Float Cage Assembly contains two

internal plastic oat balls that will rise to
shut off the air intake to the Vacuum Motor
if the wastewater level in the Recovery Tank
gets too high. This is to prevent water from
getting into the Vacuum Motor and possibly
damaging the Vacuum Motor.

, Debris Cage, Recovery Tank,

and Drain Hose.

Float Cage

Assembly

Recovery

Tank

Vacuum

Motor

Vacuum Hose

Assembly

Debris

Cage

70Service Manual – SC1500

• The Debris Cage inside the Recovery Tank

catches any large debris or particulates to
keep these materials out of the Recovery

Tank

. The debris tray cover can be removed

to clean out the Debris Cage.

• The Recovery Tank holds the wastewater
picked up by the squeegee. Note that the

Recovery Tank is hinged at the rear and tips

back for access to the Vacuum Motor. The

Drain Hose is used to drain the wastewater

from the Recovery Tank.

Drain
Hose

• The Solid State Vacuum Relay (SSR1)
controls the voltage to the Vacuum

Motor

. Note that the Solid State Vacuum

Relay

has an LED that lights when the

Relay is on.

Refer to the Squeegee System section
for more information on the squeegee
components and operation.

Recovery System 71Service Manual – SC1500

Solid State

Vacuum Relay

(SSR1)

Circuit Descriptions

Vacuum Motor Off

Bat +

SPST Key

Switch

S1

BRN/VIO

Circuit Breaker, 20 Amp

When the Vacuum Motor is off:

1

2

CB3

BLU/ORN WHT

1

2

Solid State

Vacuum Relay

3+

2+

D2

SSR1

GRA/BLKBRN

4-

1-

Control Board

Vacuum
Contactor

J3-12

Motion Input 24v

12

M4

M

Vacuum Motor

24v

A1

Bat -

J3-6

RED/WHT

Pin 6

Curtis 1210

Speed

Controller

Brake -

Bat -

E1

Bat -

• The Brake - switch on Pin 6 in the E1 Curtis Speed Controller is open and is not sending the drive signal to
the Motion Input line on pin J3-6 on the A1 Control Board.

• The Vacuum Contactor switch on pin J3-12 is open, the SSR1 Solid State Vacuum Relay is de-energized and
open, and the M4 Vacuum Motor is off.

Recovery System 72Service Manual – SC1500

Vacuum Motor On

Bat + Bat -

A1

SPST Key

Switch

BRN/VIO

Circuit Breaker, 20 Amp

S1

1

2

CB3

BLU/ORN WHT

1

2

GRA/BLKBRN

4-

3+

1-

2+

D2

SSR1

Solid State

Vacuum Relay

Vacuum Motor

Control Board

Vacuum
Contactor

J3-12

24v

Motion Input (0.1v)

12

M4

M

Bat -

J3-6

RED/WHT

Pin 6

E1

Curtis 1210

Speed

Controller

Brake -

Bat -

The following conditions must be met before the Vacuum Motor can start:

• There can be no major faults active.

• The machine must not be in a low-voltage condition.

• The Scrub System or vacuum mode must be activated (the Vacuum Mode Indicator will be on or ashing).

• The A1 Control Board must have recently detected a motion signal from the E1 Curtis Speed Controller. (The

A1 Control Board will switch off the Vacuum Motor after a maximum 10 second delay once it loses the drive

signal from the E1 Curtis Speed Controller.)

When the Operator selects a drive direction and presses the go pedal:

• The Brake - switch on Pin 6 in the E1 Curtis Speed Controller closes to ground. This drops the voltage on
the Motion Input line on pin J3-6 from 24v down to nearly 0 volts to signal the A1 Control Board that the
machine is now in motion.

• The A1 Control Board switches the Vacuum Contactor line on pin J3-12 to battery ground to energize the

SSR1 Solid State Vacuum Relay and switch on the Vacuum Motor.

Note that the output from the Vacuum Contactor line on pin J3-12 drives the SSR1 Solid State Vacuum Relay
at 100 Hz with either a 100% duty cycle for the high/standard vacuum mode, or a modulated (60%) duty
cycle to provide an average of 16.8V to the Vacuum Motor in the low/quiet vacuum mode.

“Field” Voltage Measurements with Reference to Battery Negative

Pin Number Wire Color Description Voltage

J3-12 GRA/BLK Vacuum Contactor 23.4v - Vacuum Off

6.9v - Vacuum Low/Quiet

0.104v - Vacuum High/Standard

Component Locations

The following components are included in this section:

• Recovery Tank

• Vacuum Motor

• Debris Cage

• Float Cage Assembly

• Vacuum Hose Assembly

• Drain Hose

• SSR1 Solid State Vacuum Relay

The Recovery Tank is located
underneath the control panel.

The Vacuum Motor is mounted
below the Recovery Tank.

The Debris Cage lters any
debris out of the wastewater
before it can enter the

Recovery Tank.

The Vacuum Hose Assembly
carries the wastewater from
the squeegee to the Debris

Cage

.

Float Cage

Assembly

Vacuum Hose

Assembly

(underneath

Debris Cage)

Recovery System 73Service Manual – SC1500

Vacuum Motor

(underneath

oat support)

Debris

Cage

Recovery

Tank

The Drain Hose allows you to drain the wastewater
from the Recovery Tank.

Recovery System 74Service Manual – SC1500

Drain
Hose

The SSR1 Solid State Vacuum Relay controls the
power to the vacuum motor and is located inside
the control panel assembly.

SSR1

Solid State

Vacuum Relay

Troubleshooting

Problem Cause Correction

Vacuum motor not
running - the LED
on relay SSR1 is
not on.

Vacuum motor not
running - the LED
on relay SSR1 is on.

Poor water pickup. Vacuum leak(s) due to:

No voltage from the Key
Switch S1 to terminal 3+ on
relay SSR1.

Terminal 4- on relay SSR1 is
not getting ground from the
Vacuum Contactor, pin J3­12, on the A1 Control Board.

Relay SSR1 is faulty. Replace relay SSR1.
No voltage to terminal 2+ on

relay SSR1.

No voltage from terminal
1- on relay SSR1 to the
Vacuum Motor M4.

The Vacuum Motor M4 is

not connected to battery

ground.
Relay SSR1 is faulty. Replace relay SSR1.

• Leaky vacuum hose.

• Bad recovery tank gasket.

• Drain plug not installed

correctly.

• Damaged tank.

Restrictions due to built-up
debris in the squeegee tool

or vacuum hose.

Squeegee blades worn or

out of adjustment.

Check the wiring from the Key Switch S1 to terminal

3+ on relay SSR1 and repair as necessary.

Check the wiring from pin J3-12 on the A1 Control

Board to terminal 4- on relay SSR1 and repair as
necessary.

1. Check circuit breaker CB3 and reset if necessary.

2. Check the wiring from the Key Switch S1 to circuit

breaker CB3 and repair as necessary.

Check the wiring from SSR1 to the Vacuum Motor

M4 and repair as necessary.

Check the ground connection to the Vacuum Motor

M4 and repair as necessary.

• Check the squeegee vacuum hose assembly and

tighten/replace as necessary.

• Check the recovery tank gasket and replace as

necessary.

• Make sure drain hose plug is installed correctly.

• Check the recovery tank for damage.

• Check the squeegee tool and vacuum hose
assembly for any accumulated dirt or debris and

clean as necessary.

• Check the vacuum system airow pathway
wherever the airow is forced to make a sharp turn
for any accumulated dirt or debris and clean as

necessary.

• Check and replace the squeegee blades if

necessary.

• Readjust the squeegee as necessary.

(Refer to the Squeegee Maintenance and
Squeegee Adjustments sections in the Instructions
For Use).

Recovery System 75Service Manual – SC1500

Removal and Installation

Vacuum Motor

Recovery System 76Service Manual – SC1500

1. Drain the recovery tank.

2. Lift the recovery tank to access the Vacuum

Cover

.

3. Remove the three M6 Screws, Flat Washers and

Cover Plates and remove the Vacuum Cover to

access the vacuum motor.

M6 Screw, Flat

Washer and

Cover Plate (3)

Vacuum

Cover

4. Disconnect the Vacuum Motor Electrical

Connector

.

5. Remove the Vacuum Motor from the Recovery

Tank

.

6. Reinstall the Vacuum Motor by following the

above steps in reverse order.

Note: Make sure you install the

Acoustic Insulation correctly

around the Vacuum Motor when
you reinstall the Vacuum Motor.

Recovery

Tank

Vacuum

Motor

Acoustic

Insulation

Vacuum Motor

Electrical

Connector

Service Tip: Before you reinstall the Vacuum

Cover, make sure the top of the

Vacuum Motor is centered in the

matching cutout in the Recovery

Tank

as shown.

Specications

Component Specications

Recovery System 77Service Manual – SC1500

Recovery

Tank

Vacuum

Motor

Vacuum Motor Current Draw

Sealed 40 - 44 Inches of Water

Vacuum Water Lift

1” open hole 9.5 Inches of Water

Special Tools

Vacuum water lift gauge, p/n 56205281

Low Speed: 11 - 12 Amps
High Speed: 16 - 17 Amps

Scrub System

Functional Description

The Scrub System includes the Scrub Deck, Brush or Pad Motor, Brush Motor Contactor (K2 relay) and
Deck Actuator Assembly. The Scrub System uses either disc scrub brushes or REV™ deck pads depending on
the scrub deck conguration. A 24-volt electric motor powers the brush/pad.

The scrub deck has four vertical positions:

• The scrub deck is in the fully-retracted (up) position when the machine is in the transport mode (no
scrubbing or vacuuming).

• The vacuum-only position lowers the scrub deck so the attached squeegee contacts the oor, but the
brush/pad is raised slightly above the oor. This position is used for wet vacuuming of wastewater from
the oor with no scrubbing.

• The “normal” scrub pressure position lowers the scrub deck so the brush/pad contacts the oor with
normal scrub pressure.

• The “extra” scrub pressure position lowers the scrub deck to its extension limit so the brush/pad contacts
the oor with greater than normal scrub pressure.

78Service Manual – SC1500

The SC1500 can be congured with two different scrub decks:

• The 20D Scrub Decks have a 20” brush plate assembly to
accommodate a variety of disc brushes. The 20D models can
also be used with several grades of pads by using the optional
pad holder. The brush is driven by a Brush Motor connected to
a 90-degree Gearbox.

• The 20R REV

™

Scrub Decks have a 20” pad driver for use with

REV™ deck pads only. The pad is driven directly by a 24 VDC
Motor.

Note that the two types of Scrub Decks use different Motors, but
use the same Deck Actuator Assembly and mounting hardware.

20D Scrub Deck

20R REV

™

Scrub Deck

Scrub Deck and Motor

20D Scrub Deck

Scrub System 79Service Manual – SC1500

The 20D Scrub Decks use a
horizontally-mounted Brush Motor
with an integral gearbox to drive the

Brush Plate Assembly and attached
Brush. The Brush Motor is fastened to

the Motor Spacer, which is bolted to the

Deck Lift Plate Weldment, Brush Housing

and Lower Deck Plate.
The Solution Solenoid Valve Assembly

controls the solution ow to the Brush.

The squeegee assembly snaps onto the

Squeegee Link Weldment.

The Brush Skirt helps contain the
cleaning solution.

Brush

Motor

Motor

Spacer

Squeegee

Link

Weldment

Deck

Lift Plate

Weldment

Brush

Housing

Lower

Deck Plate

Solution

Solenoid

Valve

Assembly

Brush

Skirt

Brush Plate

Assembly

Brush

(typical)

20R REV™ Deck

Scrub System 80Service Manual – SC1500

The 20R REV™ Scrub Decks use a
vertically-mounted Motor to drive the

Pad Driver Assembly and attached Pad

directly. The Motor is fastened to the

Motor Plate and attached Rev Lift Plate
Weldment

and Rev Housing.

The Solution Solenoid Valve Assembly
controls the solution ow to the Pad.

The squeegee assembly snaps onto the

Squeegee Link Weldment.

Note that the 20R REV™ Scrub Decks
require an additional connector
adaptor to plug into the scrub motor
wiring harness.

Rev

Housing

Motor

Squeegee

Link

Weldment

Rev Lift Plate

Weldment

Solution

Solenoid Valve

Assembly

Motor

Plate

Pad Driver
Assembly

Pad

(typical)

Brush Motor Contactor

The Brush Motor Contactor (K2) controls the
power to the Brush/Pad Motor.

Scrub System 81Service Manual – SC1500

Brush Motor

Contactor (K2)

Deck Actuator Assembly

The Deck Actuator Assembly uses an electric Motor to run a lead screw that
extends and retracts the Plunger. The Plunger is connected to the Scrub Deck
to raise and lower the Scrub Deck to any of four different positions:

• The fully-retracted (up) position is the Scrub Deck transport position and
is used when the Scrub and Recovery Systems are not active.

• Scrub Deck position 1 is the vacuum-only position. In this position the
Deck Actuator lowers the Scrub Deck just far enough for the squeegee
to contact the oor to pick up wastewater with the Scrub, Solution and
Detergent Systems off.

• Scrub Deck position 2 is the standard scrub pressure position.

• The fully-extended (down) position is the extra scrub pressure position.

Motor

Plunger

Deck Actuator Assembly

Two internal Position Switches, actuated by rotating Cams, provide
actuator position feedback to the A1 Control Board.

Two internal Limit Switches (top and bottom), also actuated by
rotating Cams, switch off the actuator Motor at the fully-retracted
and fully-extended positions.

Scrub System 82Service Manual – SC1500

Cams (4)

Limit

Switch

Position

Switch

Circuit Descriptions

Scrub Brush Motor

Scrub Brush Motor Off

Scrub System 83Service Manual – SC1500

Bat +

BRN

SPST Key

Switch

S1

1

BRN/VIO

A1

Control Board

Brush

WHT/RED

2

K2

Brush

Contactor

J3-13

Contactor

24v

Motion Input 24v

Brush Motor

RED

-+

M5

M

Bat -

J3-6

RED/WHT

BLK

Pin 6

E1

Curtis 1210

Speed

Controller

Brake -

Bat -

Bat -

When the machine is stationary:

• The Brake - switch on Pin 6 in the E1 Curtis Speed Controller is open and is not sending the drive signal to
the Motion Input line on pin J3-6 on the A1 Control Board.

• The Brush Contactor switch on pin J3-13 is open, the K2 Brush Contactor is de-energized and open, and the

M5 Brush Motor is off.

Scrub Brush Motor On

Scrub System 84Service Manual – SC1500

Bat + Bat -

Brush

J3-13

Contactor

RED

BRN

SPST Key

Switch

S1

1

BRN/VIO

WHT/RED

2

K2

Brush

Contactor

A1

Control Board

24v

Motion Input (0.1v)

M5

Brush Motor

-+

M

Bat -

J3-6

RED/WHT

BLK

Pin 6

The following conditions must be met before the Brush Motor can start:

• There can be no major faults active.

• The machine must not be in a low-voltage condition.

• The Scrub System must be enabled (the Solution On/Off Indicator is lighted).

E1

Curtis 1210

Speed

Controller

Brake -

Bat -

• The S7 POS 1 limit switch on the scrub deck actuator must be closed to indicate that the scrub deck is
below the vacuum-only position.

• The A1 Control Board must receive a motion signal from the E1 Curtis Speed Controller.

When the Operator selects a drive direction and presses the go pedal:

• The Brake - switch on Pin 6 in the E1 Curtis Speed Controller closes to ground. This drops the voltage on
the Motion Input line on pin J3-6 from 24v down to nearly 0 volts to signal the A1 Control Board that the
machine is now in motion.

• The A1 Control Board switches the Brush Contactor line on pin J3-13 to battery ground to energize the coil
side of the K2 Brush Contactor to close the contacts and switch on the Brush Motor.

“Field” Voltage Measurements with Reference

to Battery Negative

Pin Number Wire Color Description Voltage

J3-13 WHT/RED Brush Contactor 24.3v - Brush Motor Off

0.2v Brush Motor On

Deck Actuator Assembly

Scrub Deck Up

When the Scrub System is
switched from active to not active,
the Gang Switch in the A1 Control

Board

switches on the power to the

Brush Lift Actuator Motor M3.

Note: The Gang Switch
position determines the
polarity to run the Brush

Lift Actuator Motor

appropriate direction to
raise or lower the scrub
deck. The Gang Switch
is, in reality, a “virtual”
switch that is a type of
transistor driver circuit
in the A1 Control Board.

The Deck Actuator Assembly raises
the scrub deck until the Cam opens
the Upper Limit Switch. This shuts
off the power to the Brush Lift

Actuator Motor

.

in the

A1

Control Board

B+

B-

Gang

Switch

B-

B+

+5V

Act. Position 1 (5v)

+5V

Act. Position 2 (5v)

Scrub System 85Service Manual – SC1500

Deck Actuator Assembly

Upper

Limit

Switch

Lower

Limit

Switch

B-

J1-8

J2-12

J2-11

D YEL/BLK

C RED/VIO

F BLK/WHT

Cam

M

S7 POS 1

S6 POS 2

Brush Lift
Actuator
Motor M3

Scrub Deck in Vacuum-only Position

When the Scrub System is not
active and the Vacuum Power
Adjustment Switch is pressed to
enable the wet vacuuming mode,
the Gang Switch in the A1 Control

Board

switches on the power to the

Brush Lift Actuator Motor M3. The

Deck Actuator Assembly lowers the

scrub deck to POS (position) 1.
When the deck reaches POS 1 the

Cam closes the S7 POS 1 switch,

which drops the voltage seen
at the Act. Position 1 input from
5v to 0v. The Gang Switch then
switches polarity to run the Brush

Lift Actuator Motor

in the opposite
direction for a predetermined
period of time to compensate for
“overshoot” and position the deck
at just the right height. The A1

Control Board

then shuts off the

power to the Brush Lift Actuator

Motor

.

A1

Control Board

B+

B-

Gang

Switch

B-

B+

+5V

Act. Position 1 (0v)

+5V

Act. Position 2

Deck Actuator Assembly

Upper

Limit

Switch

Lower

Limit

Switch

B-

J1-8

J2-12

J2-11

D YEL/BLK

C RED/VIO

S7 POS 1

F BLK/WHT

S6 POS 2

M

Brush Lift
Actuator
Motor M3

Cam

Scrub Deck at Normal Scrub Pressure

When the Scrub System is active,
the Gang Switch in the A1 Control

Board

switches on the power to the

Brush Lift Actuator Motor M3. The

Deck Actuator Assembly lowers the

scrub deck to the normal scrub
pressure position, POS (position) 2.

When the deck reaches POS 2 the

Cam closes the S6 POS 2 switch,

which drops the voltage seen at
the Act. Position 2 input from 5v
to 0v. The A1 Control Board then
shuts off the power to the Brush

Lift Actuator Motor

.

A1

Control Board

B+

B-

Gang

Switch

B-

B+

+5V

Act. Position 1

Scrub System 86Service Manual – SC1500

Deck Actuator Assembly

Upper

Limit

Switch

Lower

Limit

Switch

B-

J1-8

J2-12

D YEL/BLK

C RED/VIO

S7 POS 1

M

Brush Lift
Actuator
Motor M3

Scrub Deck at Extra Scrub Pressure

When the Scrub System is active
and either the Extra Pressure
Switch or Burst of Power switch
is pressed, the Gang Switch in the

A1 Control Board switches on the

power to the Brush Lift Actuator

Motor.

The Deck Actuator Assembly
lowers the scrub deck to the extra
scrub pressure position.

When the deck reaches its lower
travel limit, the Cam opens the

Lower Limit Switch. This shuts off

the power to the Brush Lift Actuator

Motor

.

+5V

Act. Position 2 (0v)

A1

Control Board

B+

B-

Gang

Switch

B-

B+

+5V

Act. Position 1

J2-11

F BLK/WHT

S6 POS 2

Cam

Deck Actuator Assembly

Upper

Limit

Switch

Lower

Limit

Switch

B-

J1-8

J2-12

D YEL/BLK

C RED/VIO

Cam

S7 POS 1

M

Brush Lift
Actuator
Motor M3

+5V

Act. Position 2

J2-11

F BLK/WHT

S6 POS 2

Component Locations

The following components are included in this section:

• Scrub Deck

• Scrub Deck Motor

• Brush Motor Contactor (K2)

• Scrub Deck Actuator Assembly

The Scrub Deck is suspended underneath
the machine and pivots up and down on a
mechanical mount.

Scrub

Deck

Scrub System 87Service Manual – SC1500

The Scrub Deck Motor is mounted on the
top of the Scrub Deck. Note that the 20D
Scrub Deck and Brush Motor are shown
here.

Scrub Deck

Motor

Scrub

Deck

Scrub System 88Service Manual – SC1500

The Brush Motor Contactor (K2) controls the power
to the scrub deck motor and is located inside the
control panel assembly.

The Scrub Deck Actuator Assembly
is attached to the Scrub Deck and
machine frame and lowers and
raises the Scrub Deck.

Brush Motor

Contactor (K2)

Scrub Deck

Actuator

Assembly

Troubleshooting

Problem Cause Correction

Brush Motor not
running

Scrub Deck Actuator

not running.

Scrub Deck not
being lowered to

the vacuum-only
position

Scrub Deck not
being lowered to
the normal scrub

position.

No voltage to the K2 Brush
Contactor coil

No voltage through the
contacts on the K2 Brush
Contactor

No voltage to the Deck

Actuator Motor

No signal from Position
Switch 1, S7, to pin J2-12
on the A1 Control Board.

No signal from Position
Switch 2, S6, to pin J2-11 on
the A1 Control Board.

1. Check the voltage on pin J3-13 on the A1 Control
Board. The signal, referenced to ground, should

be 24.3v with the Brush Motor off, 0.2v with the

Brush Motor on.

2. Check the wiring from the Key Switch to the K2
Brush Contactor coil and repair as necessary.

1. Check circuit breaker CB4 and reset if necessary.

2. Check the coil resistance on the K2 Brush
Contactor. If the coil resistance is not 58.3 ohms
±10%, replace K2.

3. Check the continuity through the contacts on the
K2 Brush Contactor with the coil energized. If the
circuit is open, replace K2.

4. Check the wiring from battery positive to circuit

breaker CB4, and from CB4 to the K2 Brush

Contactor and repair as necessary.

5. Check the wiring from the K2 Brush Contactor to
the Brush Motor and repair as necessary.

6. Check the Brush Motor ground connection and
repair as necessary.

Check the voltage on pins J1-9 and J1-10 on the A1

Control Board. The signals, referenced to ground,

should be as follows:

Pin J1-9:

• 2.1v or 3.8v – actuator at rest

• 0.2v – actuator extending

• 22.9v – actuator retracting

Pin J1-10:

• 2.1v or 3.8v – actuator at rest

• 22.9v – actuator extending

• 0.2v – actuator retracting

Check the voltage on pin J2-12 on the A1 Control
Board. The signals, referenced to ground, should be

4.99v with the switch open and 0.03v with the switch
closed.

Check the voltage on pins J2-11 on the A1 Control
Board. The signals, referenced to ground, should be

4.99v with the switch open and 0.03v with the switch
closed.

Scrub System 89Service Manual – SC1500

Scrub System 90Service Manual – SC1500

Removal and Installation

Scrub Deck

1. Turn the key switch on, then press the Scrub On/Off Switch to lower the scrub deck to the normal scrub
position. This will relieve the tension between the scrub deck actuator and the scrub deck.

2. With the scrub deck down and the key
switch on, disconnect the Actuator Electrical

Connector

wire tie to do this.

3. Turn the key switch off.

. Note that you may need to cut a

Actuator

Electrical

Connector

4. Make sure the Ball Valve from the solution tank to the

Filter is set to the off position.

Ball

Filter

Valve

5. Loosen the Clamp and remove the

Solution Hose from the Solution
Solenoid Valve

. Note that a small

amount of solution may leak out from
the Solution Hose when you disconnect
it from the Solution Solenoid Valve.

6. Disconnect the Solenoid Electrical

Connector

.

7. Disconnect the Detergent Hose from
the Scrub Deck.

8. Remove the Vacuum Hose from the

Scrub Deck.

9. Press the rear of the Squeegee Mount

Bracket

to disengage it from the pins

on the Squeegee Link Weldment and
remove the Squeegee from the Scrub

Deck

.

Solution

Hose

Vacuum

Hose

Solution
Solenoid

Valve

Clamp

Scrub System 91Service Manual – SC1500

Solenoid

Electrical

Connector

Detergent

Hose

Scrub

Deck

Scrub

Deck

Squeegee

Mount

Bracket

10. Remove the four Shoulder Screws
holding the Lift Plate Weldment to the

Link Bar and the two Linkage Bars.

Note that you’ll need to hold the M10
Nyloc® nuts with a 17mm wrench
while you remove the Shoulder Screws.

Link Bar

Shoulder

Screw (4)

Squeegee

Mount

Bracket

Linkage

Bar (2)

Lift Plate

Weldment

11. Remove the Shoulder Screw and nut that
connect the scrub deck actuator to the Lift

Plate Weldment

on the scrub deck. Note that

you’ll need to hold the M8 Nyloc® nut with a
13mm wrench while you remove the Shoulder

Screw

.

Service Tip: Note of the rotational position of the

screw hole in the Plunger when you
remove the Shoulder Screw. Be careful
not to rotate the Plunger once the

Scrub Deck Actuator is disconnected

from the scrub deck. This can cause
the Scrub Deck Actuator to get out of
adjustment.

Scrub System 92Service Manual – SC1500

Shoulder

Screw

Lift Plate

Weldment

12. Lift up the link bar and rotate the scrub deck
slightly (counterclockwise as viewed from
the top) to get some slack in the Scrub Deck

Ground Wire

.

13. Disconnect the Scrub Deck Ground Wire from

the scrub deck.

Plunger

M8 Nyloc®

Nut

Scrub Deck

Ground Wire

Scrub Deck

Actuator

Shoulder

Screw

14. Disconnect the Scrub Deck Motor Electrical

Connector

.

15. Carefully slide the deck out of the machine.

Service Tip: The scrub motors on the
20R REV™ scrub decks are slightly
taller than the motors on 20D decks.
When you remove a 20R REV™ scrub
deck you’ll need to jack up and block the
front of the machine slightly in order
to get adequate clearance to remove the
deck from the machine.

16. Reinstall the deck by following the above
steps in reverse order.

Caution: Note that the scrub deck actuator will automatically raise the scrub deck when you

reconnect the Actuator Electrical Connector.

Scrub System 93Service Manual – SC1500

Scrub Deck Motor

Electrical

Connector

Service Tip: When you reinstall
the scrub deck, make sure you
have all 16 Link Arm Bushings
and all eight 12mm Flat Washers
installed in the Link Bar and

Linkage Bars before reinstalling

the Shoulder Bolts and Nyloc

Nuts

.

®

Link Bar

Linkage

Bar (2)

Nyloc

Nut (8)

Shoulder

Bolt (8)

12mm Flat
Washer (8)

Link Arm

Bushing (16)

Scrub System 94Service Manual – SC1500

Scrub Deck Actuator Assembly

1. Turn the key switch on, then press the Scrub On/Off Switch to lower the scrub deck to the normal scrub
position. This will relieve the tension between the scrub deck actuator and the scrub deck.

2. With the scrub deck down and the key
switch on, disconnect the Actuator Electrical

Connector

wire tie to do this.

3. Turn the key switch off.

4. Disconnect and remove the battery closest

to the scrub deck actuator to get enough
clearance to remove the actuator.

. Note that you may need to cut a

Actuator

Electrical

Connector

5. Remove the Shoulder Screw and nut that
connect the scrub deck actuator to the Lift

Plate Weldment

on the scrub deck. Note that

you’ll need to hold the M8 Nyloc® nut with a
13mm wrench while you remove the Shoulder

Screw

.

6. Remove the M10 Screw and actuator spacer

holding the Scrub Deck Actuator to the Actuator

Bracket

on the machine frame.

7. Carefully remove the Scrub Deck Actuator from
the machine.

Shoulder

Screw

Lift Plate

Weldment

M10

Screw

Actuator

Bracket

Scrub

Deck

Actuator

Service Tip: Ifyou’regoingtoreinstalltheScrub

Deck Actuator

without readjusting
the Plunger position. be careful not to
rotate the Plunger with the Scrub Deck

Actuator

out of the machine. This can
cause the Scrub Deck Actuator to get
out of adjustment.

8. Reinstall the scrub deck actuator by following the above
steps in reverse order.

Note: Ifyou’reinstallingareplacementscrub

deck actuator assembly, or if the scrub
deck actuator assembly has gotten out of
adjustment, you’ll need to set the plunger
position as described in the Scrub Deck

Actuator Adjustment subsection below.

Caution: Note that the scrub deck actuator will

automatically raise the scrub deck
when you reconnect the Actuator
Electrical Connector and battery.

Scrub System 95Service Manual – SC1500

Scrub Deck

Actuator

Plunger

Scrub Deck Actuator Adjustment

The Scrub Deck Actuator adjustment consists of setting the plunger position with the retracted travel limit
switch actuated. To set the Actuator Plunger position:

1. Drive the actuator motor to the up (fully
retracted) position using the Service Test
Mode or a jumper to the batteries.

2. Wait until the motor stops running due to
travel limit switch opening.

Note: Do not allow the Plunger to

bottom out against the motor
housing.

3. Rotate the Plunger to 10.34” (263 mm)
measured from end to end as shown.

Service Tip: Be careful not to

rotate the Plunger
prior to installing the

Scrub Deck Actuator

into the machine. This
can cause the Scrub

Deck Actuator

to get

out of adjustment.

10.34”

[263mm]

Scrub Deck Actuator

Plunger

Specications

Component Specications

Voltage – 24 VDC

Scrub System 96Service Manual – SC1500

20D Scrub Deck Brush

Motor

20R REV
Motor

K2 Brush Contactor Nominal Coil Resistance – 58.3 ohms ±10%

™

Scrub Deck

RPM – 140
Current Draw – 20 Amps
Output Power – 380 Watts / 1/2 HP

Voltage – 24 VDC

RPM – 2200

Current Draw – 28 Amps

Output Power – 560 Watts / 3/4 HP

Voltage – 24 VDC

Output Power – 1/6 HP

Total Travel – 4.00” ±0.15”

Scrub Deck Actuator

Gearbox Ratio – 20.23:1

Performance Data

Thrust – 0 lbs.

No load

Full load

Starting Thrust – 700 lbs.

Speed – 42.5 in/min

Current Draw – 1.8 ±1.0 Amps max.

Thrust – 600 lbs.

Speed – 34 in/min

Current Draw – 7.0 ±1.0 Amps

Solution System

Functional Description

The Solution System is a gravity-feed system that supplies cleaning solution to the scrub brush/pad on the
scrub deck. The detergent, supplied from the detergent tank and pump, is added to the solution upstream
of the scrub deck. The Solution Solenoid Valve controls the solution ow to the scrub deck. The A1 Control
Board sends a pulsed voltage signal to the Solution Solenoid Valve that opens and closes the Valve to
regulate the solution ow according to the ow rate selected with the solution ow adjustment switch.

The Solution System includes the Solution Tank, Water Filter, Solution Solenoid Valve Assembly and
associated valves and hoses.

Solution Tank, Water Filter and Valves

The Solution Tank holds
approximately 12 gallons [45
liters] of water/solution.

97Service Manual – SC1500

The Ball Valve controls the
solution ow to the Water Filter
and downstream Solution Hose
that is plumbed to the Solution
Solenoid Valve.

The Water Filter can be
disassembled for cleaning.

Solution

Tank

Solution Hose

(to Solution

Solenoid Valve)

Water

Filter

Ball

Valve

Solution Solenoid Valve

The L1 Solution Solenoid Valve controls the solution ow to the
scrub deck. The solution from the solution tank enters the L1

Solution Solenoid Valve

the rear port to the scrub deck as shown.
The two wires in the Electrical Connector get power from

the key switch and pin J3-11 - Solution Solenoid on the A1
Control Board.

The A1 Control Board sends a modulated signal through
Pin J3-11 to switch the L1 Solution Solenoid Valve to ground
and open the L1 Solution Solenoid Valve for a period of time
corresponding to the selected solution ow rate. The period of
time during which the solution solenoid is energized (open) is
referred to as the “duty cycle” and is a percentage of the total
six-second cycle.

through the side port and exits through

Solution System 98Service Manual – SC1500

Electrical

Connector

Outlet to

Scrub Deck

For example, a 50-percent duty cycle would energize and open
the L1 Solution Solenoid Valve for three seconds during every
six-second cycle.

Note: 100 percent duty cycle is full solution

owwiththeL1 Solution Solenoid Valve
continuously open.

Inlet from

Solution Tank

L1 Solution

Solenoid

Valve

Detergent System

The Detergent System uses an electric diaphragm

Detergent Pump to inject detergent from the
Detergent Cartridge into the cleaning solution

upstream of the scrub deck. The A1 Control Board
sends voltage pulses to the Detergent Pump that
alternate polarity to move the pump plunger and
diaphragm in and out to control the Detergent

Pump

output. This allows the A1 Control Board
to inject the correct amount of detergent for the
solution ow rate and detergent percentage/ratio
selected by the Operator.

Solution System 99Service Manual – SC1500

Detergent

Pump

Detergent

Cartridge

Circuit Descriptions

Solution Solenoid Valve Off

Bat +

BRN/VIO

Solution Line from

Solenoid Valve

to Scrub Deck

1

SPST Key

Switch

S1

Solution System 100Service Manual – SC1500

2

A1

Control Board

VIO/BLK

J3-11

Solution
Solenoid

Bat -

E1 Curtis

1210 Speed

Controller

+24v

Motion Input 24v

J3-6

RED/WHT

Pin 6

Brake -

Bat -

L1 Solution

Solution Line from

Solution Tank

Solenoid Valve

(closed)

When the machine is stationary:

• The Brake - switch on Pin 6 in the E1 Curtis Speed Controller is open and is not sending the drive signal to

the Motion Input line on pin J3-6 on the A1 Control Board.

• The Solution Solenoid switch on pin J3-11 is open, and the L1 Solution Solenoid Valve is de-energized and

closed. This prevents solution ow from the solution tank to the scrub deck.

If the Solution System is disabled, the Solution Solenoid switch on pin J3-11 will remain open regardless of
whether or not the A1 Control Board receives a drive signal from the E1 Curtis Speed Controller.