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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:






L3-L4:






Normal Operation
During normal operation, the EATC or EMTC activates the rear window defrost relay by providing grounding the relay coil through circuit CH122 (WH/OG). When the defrost relay is activated, power is supplied from the rear window defrost relay through circuit CRD06 (BN/YE) to the rear window defrost grid. Ground is supplied to the rear window defrost grid through circuit GD150 (BK/WH).

Possible Causes
- Short to voltage in circuit CRD06 (BN/YE)
- Short to ground in circuit CH122 (WH/OG)
- Rear window defrost relay
- EATC or EMTC
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