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Test J: The Defrost System Will Not Shut Off Automatically

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

Normal Operation
During normal operation, the heating ventilation air conditioning (HVAC) module - electronic automatic temperature control (EATC) or HVAC module - electronic manual temperature control (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).

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Rear window defrost relay
- HVAC module - EATC or HVAC module - EMTC


J1-J2:






J3-J4: