Diagnostic Fault Information
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2007 GMC Yukon XL, 2007 GMC Yukon, 2007 Chevrolet Tahoe, 2007 Chevrolet Suburban, and 2007 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
DTC B3891
| Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
| Rear Fog Lamp Switch Signal Circuit | B3891 02 | B3891 05 | B3891 05 | - |
| Rear Fog Lamp Ground Circuit | - | B3891 05 | - | - |
| Rear Fog Lamp Switch Signal Circuit | 1 | 2 | - | - |
| Rear Fog Lamp Switch Ground Circuit | - | 2 | - | - |
| 1. Fog Lamp Always On - Rear 2. Fog Lamp Inoperative - Rear |
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