Test F: Left PRETENSIONER Circuit Short To Battery Or Ignition (DTC B1878): Description
WARNING: This page is about a different car, the 2002 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
Restraints Control Module (RCM) monitors circuits to left seat belt pretensioner. When RCM detects a circuit short to battery, it will store Diagnostic Trouble Code (DTC) B1878 in memory and flash Code 17 on AIR BAG warning light.