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Pinpoint Test 1: The Air Bag Indicator Is Illuminated Continuously/No Communication With the Restraints Control Module (RCM)

PINPOINT TEST 1: THE AIR BAG INDICATOR IS ILLUMINATED CONTINUOUSLY/NO COMMUNICATION WITH THE RESTRAINTS CONTROL MODULE (RCM)

Normal Operation
During normal operation, the instrument cluster module will illuminate the air bag indicator continuously for 6 seconds after the ignition switch is placed to the RUN or ON position. If the supplemental restraint system (SRS) is fault free, the air bag warning indicator will turn off and remain off. If a fault is detected in the SRS, the air bag warning indicator will illuminate and remain illuminated for the rest of the key cycle. The restraints control module (RCM) will communicate to the instrument cluster module via the high-speed controller area network (HS-CAN). The instrument cluster module will illuminate the air bag indicator based on messaging from the RCM or if there is no communication between the RCM and instrument cluster module.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Instrument cluster module.
- RCM

WARNING: Always tighten the fasteners of the restraints control module (RCM) and impact sensor (if equipped) to the specified torque. Failure to do so may result in incorrect restraint system operation, which increases the risk of personal injury or death in a crash.

NOTE:
- Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test.
- Supplemental restraint system (SRS) components should only be disconnected or reconnected when instructed to do so within a pinpoint test step. Failure to follow this instruction may result in incorrect diagnosis of the SRS.
- The SRS must be fully operational and free of faults before releasing the vehicle to the customer.

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