LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Cadillac >> 2009 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 234 (Lighting System) >> Diagnostic Information and Procedures >> DTC B3891 >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2010 GMC Yukon XL, 2010 GMC Yukon, 2010 Chevrolet Tahoe, 2010 Chevrolet Suburban, and 2010 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
  1. Inspect the trailer rear fog lamp bulb for an open or shorted filament.
    • If the bulb is inoperable, replace the bulb.
  2. Park lamp switch OFF, clear the DTC, test the trailer rear fog lamp circuit for a short to voltage, short to ground, an open, or high resistance.
    • If all circuits/connections test normal, replace the XBCM.
scientia non olet · About LEMON Manuals