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Defogger/Rear Wiper Switch - Become Hot


91chevy20

GMC NUMBER: 91-8A-127

GROUP: 8A Cab Electrical

DATE: July, 1991

CORPORATE
NUMBER: 168101


SUBJECT: REAR WINDOW DEFOGGER SWITCH AND REAR WINDOW WIPER SWITCH BECOME HOT TO TOUCH

MODELS: 1991 S/T UTILITY VEHICLES


Some owners of 1991 S/T utility models may comment on a condition where the rear window defogger switch and/or the rear window wiper switch is hot to the touch after the dash lights have been on for a period of time. This condition was corrected in production through the introduction of new switch assemblies which have bulbs that operate at lower temperatures. Vehicles built after the VIN breakpoints listed below have been built with the latest design switches.

Plant GMC Chevrolet Oldsmobile
Pontiac West M0529589 M0198875 -
Moraine M2548564 M2272059 M2704676
Shreveport M8540761 M8257710 -

If this condition occurs, a new rear window defogger switch and/or rear window wiper switch should be installed to replace the affected part.

SERVICE PROCEDURE:

1. Disconnect negative battery cable.

2. Remove trim plate retaining screw.

3. Remove trim plate.

4. Disconnect wiper/defogger switch connector(s).


5. Remove switch(s) from trim plate.

6. Install new switch(s).

7. Reconnect wiring connector(s).

8. Reinstall trim plate in dash.

9. Reinstall retaining screw.

10. Reconnect negative battery cable.

SERVICE PARTS INFORMATION

Part
Number Description Quantity
15679578 Rear window defogger 1
switch
15679579 Rear window wiper switch 1

Parts are currently available from GMSPO.

WARRANTY INFORMATION

For vehicles repaired under warranty use:

Labor Labor
Operation Description Time
R2110 Switch rear defogger, 0.2 hr.
replace
N2611 Switch rear wiper, replace 0.2 hr.