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Test M: LFC 14/B1921 - Air Bag Diagnostic Monitor Ground Circuit Open

PINPOINT TEST M: LFC 14/B1921 - AIR BAG DIAGNOSTIC MONITOR GROUND CIRCUIT OPEN


M1-M2:






M2-M5:






M6-M7:






Normal Operation
The restraints control module (RCM) monitors the resistance between the ground connections at the mounting bracket and the reference ground at C310a pin 16, circuit 1203 (BK/LB).

If the RCM detects a difference in resistance, it will store diagnostic trouble code (DTC) B1921 in memory and flash lamp fault code (LFC) 14 (or higher priority code if one exists) on the air bag warning indicator.

Possible Causes
A resistance difference between the RCM bracket ground and harness ground can be caused by:
- RCM bracket not securely mounted.
- faulted wiring, terminals or connectors.
- a faulted RCM.