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Test L: The Defrost System Will Not Shut Off Automatically

PINPOINT TEST L: THE DEFROST SYSTEM WILL NOT SHUT OFF AUTOMATICALLY


L1-L3:






Normal Operation
During normal operation, the ICM activates the rear window defrost relay by providing grounding the relay coil through circuit 1009 (OG/YE). When the defrost relay is activated, power is supplied from the rear window defrost relay through circuit 186 (BN/LB) to the rear window defrost grid. Ground is supplied to the rear window defrost grid through circuit 57 (BK).

Possible Causes
- Short to voltage in circuit 186 (BN/LB)
- Short to ground in circuit 1009 (OG/YE)
- Rear window defrost relay
- ICM