Test Y: DTC B1921 - Air Bag Diagnostic Monitor Ground Circuit Open

PINPOINT TEST Y: DTC B1921 - AIR BAG DIAGNOSTIC MONITOR GROUND CIRCUIT OPEN

Y1-Y4:

Y5-Y6:

WARNING: The tightening torque of the restraints control module (RCM) retaining bolts is critical for correct air bag supplemental restraint system (SRS) operation. Refer to Restraints Control Module (RCM) for correct torque values.

NOTE: A resistance difference as low as 25 ohms can set the DTC.

Normal Operation
The restraints control module (RCM) monitors the resistance of the case ground. If the RCM detects a difference in resistance, it will store diagnostic trouble code (DTC) B1921 in memory and illuminate the air bag indicator.

Possible Causes
An air bag diagnostic monitor ground circuit open can be caused by:
- an RCM or RCM bracket that is not securely mounted.
- damaged wiring, terminals or connectors.
- a faulted RCM.