Pinpoint Test J : The Defrost System Will Not Shut Off Automatically: Notes
WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.
Refer to Heated Window , for schematic and connector information.
Normal Operation
With the engine running, the HVAC module 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).
- DTC B1C83:11 (Rear Defog Relay: Circuit Short To Ground) - Sets when a short to ground is detected on the relay control circuit by the HVAC module.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Rear window defrost relay
- HVAC module