Pinpoint Test A : The Defrost System Is Inoperative: Notes
WARNING: This page is about a different car, the 2019 Ford F-550 Super Duty, 2019 Ford F-450 Super Duty, 2019 Ford F-350 Super Duty, and 2019 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
The Defrost System is Inoperative
Refer to Heated Window for schematic and connector information.
Normal Operation and Fault Conditions
REFER to: Glass, Frames and Mechanisms - System Operation and Component Description .
DTC Fault Trigger Conditions
| DTC | Description | Fault Trigger Conditions |
|---|---|---|
| B1C83:12 | Rear Defog Relay: Circuit Short to Battery | This DTC sets when the FCIM detects a short to voltage on the rear window defrost relay control circuit. |
| B1C83:14 | Rear Defog Relay: Circuit Short To Ground or Open | This DTC sets when the FCIM detects an open or short to ground on the rear window defrost relay control circuit. |
Possible Causes
- Fuse
- Rear window defrost relay
- Wiring, terminals or connectors
- Rear window defrost grid
- FCIM
Visual Inspection and Diagnostic Pre-checks
- Verify BJB fuse 12 (40A) is OK.
- Inspect the rear window defrost grid and electrical connectors for damage.