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Test O: DTC B1868 - Lamp Air Bag Warning Indicator Circuit Failure

PINPOINT TEST O: DTC B1868 - LAMP AIR BAG WARNING INDICATOR CIRCUIT FAILURE


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Normal Operation
During normal operation, the air bag warning indicator will illuminate continuously for approximately 6 seconds and then go out after the ignition switch is placed in the ON position and no air bag fault exists. Control of the air bag warning indicator is a function of the instrument cluster module based on information it receives from the restraints control module (RCM) over the HS-CAN. The default mode for the air bag warning indicator is on. The RCM sends a message to the instrument cluster module to turn the indicator off if no air bag fault exists. If the RCM detects a problem with the supplemental restraints system it will send a message to the instrument cluster module to turn the air bag indicator warning lamp on.

If the instrument cluster module detects a problem with the air bag warning indicator it will send a fault message to the RCM and the RCM will store diagnostic trouble code (DTC) B1868 in memory.

Possible Causes
A lamp air bag warning indicator circuit failure can be caused by:
- a faulted instrument cluster.
- a faulted RCM.