Test E: The Defrost System Is Inoperative

PINPOINT TEST E: THE DEFROST SYSTEM IS INOPERATIVE

Normal Operation
The heated rear window is controlled by the HVAC module. The ignition switch must be in RUN for the defrost system to operate. When the rear window defrost button is pressed, the HVAC module provides a ground for the rear window defrost relay coil through circuit 688 (GY/LB). The rear window defrost relay coil is energized, providing battery voltage to the antenna module on circuit 186 (BN/LB). The antenna module then supplies voltage and ground to the heated rear window grid.

This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- Rear window defrost relay
- Antenna module
- Heated rear window grid
- HVAC module

E1-E2:

E2-E3:

E3 Continued:

E4-E5:

E6-E7:

E7-E8: