Test G: The Defrost System Is Inoperative

PINPOINT TEST G: THE DEFROST SYSTEM IS INOPERATIVE

G1-G2:

G2-G3:

G3-G5:

G5-G6:

G6-G8:

G8-G11:

G11-G13:

G13-G14:

G15-G16:

Normal Operation
For the hard top defrost system, the rear electronic module (REM) checks circuit 9-HB23 (BN/WH) for a ground. If circuit 9-HB23 (BN/WH) is grounded, the REM commands the hard top system to operate when the heated rear window switch is pressed. The rear battery junction box (BJB) heated rear window relay has voltage at all times. The heated rear window switch supplies a signal to the REM which grounds the rear BJB heated rear window relay and closes it in order to supply voltage to circuit 75-HB19 (YE/RD), which supplies voltage to the heated rear window grid. The grid is grounded through circuit 31-HB19 (BK/BU). The rear BJB heated rear window relay remains closed, supplying voltage to the heated rear window grid for approximately 10 minutes or until the heated rear window switch is pressed again.

For the convertible top defrost system, the REM checks circuit 9-HB23 (BN/WH) for a ground. If circuit 9-HB23 (BN/WH) is not grounded, the REM commands the convertible top system to operate when the heated rear window switch is pressed.

The auxiliary relay box heated rear window relay has voltage at all times. The heated rear window switch supplies a signal to the REM which grounds the auxiliary relay box heated rear window relay and closes it in order to supply voltage to circuit 75-HB20 (YE/GN), which powers the heated rear window grid.

The auxiliary relay box heated rear window relay remains closed, supplying voltage to the heated rear window grid for approximately 10 minutes or until the heated rear window switch is pressed again.

Possible Causes
- circuit 9-HB19 (BN/RD) open
- circuit 9-HB23 (BN/WH) open
- circuit 91-HB24 (BN) open
- circuit 91S-HB23 (BN/WH) open
- circuit 30-HB23 (RD/WH) open
- circuit 75-HB20 (YE/GN) open
- circuit 30-HB24 (RD/YE) open
- circuit 75-HB19 (YE/RD) open
- circuit 31-HB19 (BK/BU) open
- heated rear window switch (part of the DATC)
- heated rear window relays
- REM
- convertible top rear window glass
- removable top rear window glass