Test O: Left Seat Belt Buckle Switch Circuit Fault (DTC B2691): Description
WARNING: This page is about a different car, the 2004 Mercury Mountaineer and 2004 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
Restraints Control Module (RCM) checks left seat belt circuits for faults. If RCM detects an open circuit or short to battery fault, it will store DTC B2691 in memory and flash Code 51 on AIR BAG warning light.