Test G: The Defrost System Is Inoperative

PINPOINT TEST G: THE DEFROST SYSTEM IS INOPERATIVE

G1-G3:

G3-G5:

G5-G7:

G7-G8:

G8-G9:

G9-G11:

Normal Operation
The heated rear window operates only when the engine is running. The heated rear window relay coil is grounded by the rear electronic module (REM) when the module receives a standard corporate protocol (SCP) bus signal from the digital automatic temperature control (DATC) module to turn on the heated rear window. The heated rear window relay has battery voltage to it at all times on circuit 30-HB23 (RD/WH). When the REM grounds the relay coil and closes the relay, it supplies voltage to the heated rear window over circuit 15S-DA13 (GN/YE) to circuit 15S-HB19 (GN/BU) through the heated rear window capacitor jumper circuit.

Possible Causes
- fuse
- circuit 15S-DA13 (GN/YE) open
- circuit 15S-HB19 (GN/BU) open
- circuit 30-HB23 (RD/WH) open
- circuit 91S-HB23 (BN/WH) open
- heated rear window relay
- battery junction box (BJB)
- DATC module
- REM
- heated rear window capacitor jumper circuit