C.E. Niehoff & Co. C505 Troubleshooting Guides

C505, C527, C531, and C534 Alternators

C.E. Niehoff & Co.

Before troubleshooting any CEN products, the service technician should:

WARNING

• read, understand, and agree to follow all information contained in this troubleshooting guide.

• understand the operational characteristics of the electrical charging system components to be tested.

• be proﬁ cient at the use of tools and test equipment used in troubleshooting CEN products.

Troubleshooting Guide

Hazard Definitions

These terms are used to bring attention to presence of hazards of various risk levels or to important information concerning product life. Indicates presence of hazard(s) that

WARNING

can cause severe personal injury, death, or substantial property damage if ignored.

Indicates presence of hazards that

CAUTION

will or can cause minor personal injury or property damage.

Table of Contents

Section A: Description and Operation ....................... 2-3

Section B: Schematic Diagram ................................. 4-5

Section C: On-Vehicle Troubleshooting ..................... 6-8

Tools and Equipment

• Digital Multimeter (DMM)

• Ammeter (digital, inductive)

• Jumper wires

• CEN 5-pin Round Inline Harness Test Tool A10-140

Figure 1—CEN 5-pin Round Inline Harness Test Tool

A10-140

Testing Guidelines

Professional service technicians rely on the following guidelines when testing electrical components.

Voltage testing:

• Set meter to proper scale and type (AC or DC).

• Be sure to zero the meter scale or identify the meter burden by touching meter leads together. Meter burden must be subtracted from final reading obtained.

• Be sure the meter leads touch source area only. Prevent short circuit damage to test leads or source by not allowing meter leads to touch other pins or exposed wires in test area.

• Be sure to use CEN tools designed especially for troubleshooting CEN alternators when available. See page 1 for more information.

Resistance (ohm) testing:

• Set meter to proper scale.

• Be sure to zero the meter scale or identify the meter burden by touching meter leads together. Meter burden must be subtracted from final reading obtained.

• Be sure the meter leads touch source area only. Prevent altering the reading by not allowing fingers or body parts to touch meter leads or source during reading.

• Be sure reading is taken when source is at 70ºF. Readings taken at higher temperatures will increase the reading. Conversely, readings taken at lower temperatures will decrease the reading.

• Be sure to test directly at the source. Testing through extended harnesses or cable extensions may increase the reading.

Voltage drop testing:

• Measure voltage between B+ on alternator or source and B- (ground) on alternator or source. Record obtained reading. Move to batteries or other source and measure again between B+ and B- terminals on battery or other source. Difference between the two readings represents voltage lost within the circuit due to but not limited to inadequate cable gage or faulty connections.

• Voltage drop measurements must be taken with all electrical loads or source operating.

Dynamic/Live testing:

Definition: Connecting power and ground to a component to test operation/function out of circuit.

1. Be sure to connect jumper leads directly and securely to source contacts of the component being tested.

2. Be sure to make any connection to power and ground at the power supply or battery source terminals. Do not make connection at component source terminals as that may create an arc and damage component source terminals.

TG70C

Page 1

Section A: Description and Operation

CEN C505, C527, C531, and C534 Alternators/Regulators Description and Operation

C505, C527, C531, and C534 14 V (360 A) alternators are internally rectified. All windings and current-transmitting components are non-moving, so there are no brushes or slip rings to wear out.

• When controlled by the A2-334 (C505, C527 or C531 alternator-mounted) or A2-335 (C527 or C531 remote-mounted)

regulator, after engine is running, the alternator is externally energized when the battery master switch on the vehicle is turned on and regulator receives energize signal through IGN terminal. Regulator monitors alternator rotation and provides field current only when it detects alternator shaft rotating at or above idle speed. After regulator detects alternator rotation, it gradually applies field current, preventing an abrupt mechanical load on accessory drive system.

The soft start may take up to 20 seconds.

• When controlled by the A2-343 (C527 alternator-mounted), A2-348 (C527, C531, or C534 alternator-mounted) or A2-350 (C527, C531, or C534 remote-mounted) regulator, the alternator is externally energized when the battery master switch on the vehicle is turned on and provides power to the regulators through the IGN circuit; can also operate without vehicle connection to the IGN circuit, and instead provide power by sensing rotation through the regulator’s AC circuit.

After field coil is energized. AC is rectified into DC output through diodes in rectifier housing and supplied to the battery through the alternator B+ circuit. See schematic diagrams on pages 4 and 5. Alternator output current is self-limiting and will not exceed rated capacity of alternator. Regulator maintains alternator output voltage at pre-determined regulated setting (see Table 1 or 2 below for setpoints) as vehicle electrical loads are switched on and off.

A2-334 and A2-335 regulators furnished with some units include:

• External IGN terminal for energize connection.

• P terminal that can provide optional AC voltage tap. P terminal signal frequency (Hz) x 10 = alternator shaft rpm.

• Tricolored LED. See page 6.

• Regulator fixed (flat temperature compensation) setpoints shown in Table 1 are selected based on battery type. Battery type selection and battery maintenance/function are the sole responsibilities of the customer.

Table 1 — A2-334 & A2-335 Regulator Setpoint Switch Position

Voltage Setpoint (±0.2 V)* Battery Type*

Position 1 14.0 V Maintenance (D Category)

Position 2 14.4 V Maintenance-free (Group 31)

Position 3 14.8 V Maintenance-free (Group 31)

Position 4 15.5 V Battery Isolator in Charging System

* Voltage setpoint can depend on temperature or climate condition, as well as battery type. If boiling or excessive gassing occurs with higher voltage setpoint, change to next lower voltage setpoint.

Figure 2—Voltage Setpoints

A2-343, A2-348, and A2-350 regulators furnished with some units includes:

• (A2-343 only) No external terminals, only a special 3-pin vehicle harness connector providing one pin for optional AC voltage tap (PHASE OUT), one pin for DC voltage signal to vehicle electrical system confirming alternator operation (D+), and one pin for the ignition connection (IGN). This regulator can function with or without vehicle ignition. When necessary, IGN circuit in vehicle 3-pin harness is connected to vehicle ignition to provide battery voltage when engine is running. Circuit should be off (no voltage present) when vehicle ignition is off or engine is not running.

• (A2-348 & A2-350 only) P terminal that can provide optional AC voltage tap. P terminal signal frequency (Hz) x 10 = alternator shaft rpm.

• (All models) Overvoltage cutout (OVCO). See pages 6-7.

• (All models) Tricolored LED. See page 6.

• (All models) Battery type selection and battery maintenance/function are the sole responsibilities of the customer.

• (All models) Temperature-voltage sense/J1939 connector to be used with optional harness.

— When temperature-voltage sense/J1939 harness is not connected, regulator will operate in fixed voltage setting

determined by the select switch position on the bottom of the regulator. See Column 2 in Table 2. — When temperature-voltage sense/J1939 harness is connected, regulator will automatically optimize the charge volt age for battery type based on temperature. Also, vehicle manufacturer-requested functions of J1939 interface are available through connector. See Column 3 in Table 2.

Table 2 — A2-343, A2-348, & A2-350 Regulator Voltage/Battery Switch Position

T-VS/J1939 Harness Not

Switch Position

Position 1 13.8 V Maintenance (D Category)

Position 2 14.0 V Maintenance-free (Group 31)

Position 3 14.3 V AGM

Position 4 14.5 V

Connected (Voltage Select)

Page 2

T-VS/J1939 Harness Connected

(Battery Select)

DO NOT USE POSITION # 4

Figure 3—Voltage Setpoints/

Battery Selection

TG70C

Section A: Description and Operation (CONT’D)

B+ terminal

B– terminal

Figure 4 —C505 Alternator with

A2-334 Regulator Terminals

IGN terminal

LED

Alternatorto-regulator connector

Alternator-toregulator connector

Vehicle connector

Battery-voltage sense/J1939 connector

LED

Figure 7 — A2-343

Regulator Connections

Regulator Terminals (A2-335 shown)

Alternatorto-regulator connector

Battery-voltage sense/J1939 connector

Figure 6 — C527/C531 Alternator with

A2-348/A2-350 Regulator Terminals

P terminal

Figure 5 — A2-334/A2-335

Regulator P terminal

B– terminal

(A2-348 shown)

B+ terminal

Regulator P terminal

Battery-voltage sense/J1939 connector

Alternatorto-regulator connector

Figure 8 — C534 Alternator with

A2-348/A2-350 Regulator Terminals

(A2-348 shown)

B+ terminal

B– terminal

TG70C

Page 3

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