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Test H: The Defrost System Does Not Shut Off Automatically

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


H1-H4:






H4-H5:






Normal Operation
The heated rear window relay coil stays grounded by the rear electronic module (REM) for approximately 10 minutes, after which the REM removes the ground to circuit 91S-HB23 (BN/WH), thereby opening the heated rear window relay. This disconnects the voltage from circuits 15S-DA13 (GN/YE) and 15S-HB19 (GN/BU), which powers the heated rear window.

Possible Causes
- circuit 15S-DC1 (GN/YE) short to voltage
- circuit 29-HB1 (OG/YE) short to voltage
- circuit 91S-HB23 (BN/WH) short to ground
- heated rear window relay
- REM
- DATC module