FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Test G: The Defrost System Does Not Shut Off Automatically

PINPOINT TEST G: THE DEFROST SYSTEM DOES NOT SHUT OFF AUTOMATICALLY

Normal Operation
The key must be in the START or RUN position for the heated rear window to operate. When the rear window defrost switch is pressed, a momentary ground is supplied to the driver's door module (DDM) through circuit 1010 (DB/OG). The DDM provides a ground for the rear window defrost relay coil on circuit 688 (GY/LB). When the rear window defrost relay coil is energized, the relay switch closes, providing voltage to the heated rear window grid, the heated rear window indicator, and the heated exterior mirror (if equipped) through circuit 186 (BN/LB). The heated rear window grid and the rear window defrost switch are grounded through circuit 57 (BK).

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Rear window defrost switch
- Rear window defrost relay
- DDM


G1-G3:






G3-G4:






G4-G5:






G5-G7: