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Test T: LFC 36/DTC B1993 - Driver Side Air Bag Circuit Short to Gnd.

T1 - T2:






T2 - T3:






T4 - T5:






T5:






T6 - T7:






T8:






Normal Operation
The Restraints Control Module (RCM) monitors the resistance to ground at RCM C1 pins 2 and 3. If the resistance is less than 1000 ohms at either pin, the RCM will interpret that as a ground short, store Diagnostic Trouble Code (DTC) B1993 and flash Lamp Fault Code (LFC) 36.

Possible Causes
A driver side air bag circuit short to ground can he caused by:
^ grounded wiring on circuit 1257 (WH/LB).
^ damaged wiring on circuit 1258 (BN/LB).
^ ground short in the driver side air bag module.
^ an RCM internal concern.