Test D: Left PRETENSIONER Circuit Resistance High Or Low (DTC B1877 Or B1885): Description
WARNING: This page is about a different car, the 2004 Ford Econoline. However, it is still accessible from the selected car via links, so may be relevant.
Restraints Control Module (RCM) monitors resistance of circuits to left seat belt pretensioner. When RCM detects resistance that is out of the expected range (high or low), it will store Diagnostic Trouble Code (DTC) B1877 or B1885 in memory and flash Code 33 on AIR BAG warning light.