SHARP R18XXFFCC, R-1870F, R-1870TF, R-1871F, R-1872F Service Manual

SUPPLEMENTAL SERVICE MANUAL

S75M262R187XF

MICROWAVE OVENS

R-1870F, R-1870TF, R-1871F, R-1872F,

R-1874F, R-1874TF, R-1875F

This is a supplemental Service Manual for Microwave Oven models:

R-1870F, R-1870TF, R-1871F, R-1872F, R-1874F, R-1874TF and R-1875F.

These models are quite similar to the base models:

R-1870, R-1871, R-1872, R-1874 and R-1875.

This supplemental manual must be used in conjunction with the base model service manual for
complete operation, service, safety and replacement parts information.

This supplemental manual is being issued to comply with the new FCC standards, that all
Microwave models produced from July 2005 must have a noise filter unit included, plus any
associated parts.

In the interest of user-safety the oven should be restored to its original condition and only parts identical to those specified
should be used.

WARNING TO SERVICE PERSONNEL: Microwave ovens contain circuitry capable of producing very high voltage and
current, contact with following parts may result in a severe, possibly fatal, electrical shock. (High Voltage Capacitor,
High Voltage Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc..)

SHARP ELECTRONCS CORPORATION

Service Headquarters: Sharp Plaza, Mahwah, New Jersey, 07430-2135

This document has been published to be used for after
sales service only.
The contents are subject to change without notice.

MAGNETRON
TEMPERATURE

YLW

FUSE

RED

CONTROL UNIT

A5

C1A3A1

GRY

GRY

RED or PNK

BRN

HL

120VAC
60Hz

C3

BLK

BRN

or

RED

HOOD FAN
THERMAL
CUT OUTS

GRY

GRY

BRN

YLW

NOISE

RESISTOR

BLK

WHT

RED

or
PNK

BLU

HOOD
MOTOR

RED

PNK

RY9

C9

C5

RY10

C7

HOOD

PPL

CAPACITOR

RED

YLW

HOOD

BRN

LAMP

HL

GRY

BLK

BLK

BLK

MONITOR

FUSE (20A)

"TO SOURCE"

"TO SOURCE"

NOISE
FILTER

YLW

(CONV. SIDE)

RED

BLK

"TO LOAD"

C2

C3

"TO LOAD"

GRY

GRY

BLK

H

GRN
GRN

GND

R2

C1

N

WHT

Notes

1. Circuits / Wire Colors subject to change without notice.

2. Terminal with projection or opposite blue mark on lamp socket
must be connected to neutral wire.

3. Only certain models use the absolute humidity sensor.

4. Power transformer top (finish lead) terminal must be connected to the hot (BLK) wire.

NEW SCHEMATIC

COM

BLK

RY1

N.O.

GRY
GRY

ORG

TTM

TURNTABLE MOTOR

WHT

SECONDARY
INTERLOCK
SWITCH

WHT
WHT

CONVECTION MOTOR

B7B1B3

RY1

BLK or BRN

WHT

YLW

OLCM

WHT

GRY

GRY

B5

BLU

RED

FM

DM

FAN MOTOR

DAMPER MOTOR

GRY

GRY

GRY

RY1RY7RY4RY5RY6RY8

COM
RY2

BRN YLW

OVEN LAMP

COM
RY3

BRN PPL

RY3 RY2

N.O.
RY3

PPL

RED

HEATING
ELEMENT

WHT

E1

RED or PNK

DOOR
SENSING
SWITCH

BLK BLK

PRIMARY

E2

GRN

N.O.
RY2

INTERLOCK RELAY

BLK or BRN

GRN

THERMISTOR

AH SENSOR

F1 F2

BRN

BLK or BRN

SWITCH

E3 E4E6E5

DAMPER

F3

WHT

WHT

MONITOR
SWITCH

WHT

STIRRER MOTOR

STM

BLK or BRN

WHT

WHT

POWER
TRANSFORMER

BLK

BLK/ BLK or BRN

WHT

WHT

HIGH
VOLTAGE
CAPACITOR
XXX μF

HIGH
VOLTAGE
RECTIFIER

MAGNETRON

R-1870F, R-1870TF, R-1871F, R-1872F CHANGED PARTS

FW-VZB278MRE0 Main wire harness 1 AX
FPWBFA380WRKZ Noise filter unit 1 AM
LANGQB025MRP0 Noise unit angle 1 AE

Monitor switch

and

fuse assembly

Main wire harness

Noise filter unit

Noise unit angle

Actual wire harness may be different from illustration.

Monitor switch

and

fuse assembly

R-1874F, R-1874TF, R-1875F CHANGED PARTS

No change