Blown Air Bag Warning Light bulb
Air Bag Warning Light bulb harness is open or shorted
Air Bag Warning Light bulb circuit poor electrical connection
Faulty Restrain Control Module (RCM)
Air Bag Warning Light ON
The air bag indicator is designed to illuminate for 6 (±2) seconds when the ignition switch is turned to the RUN position. This initial 6 seconds of illumination is considered normal operation and is called Prove-Out of the air bag indicator. The air bag indicator is then used to warn the driver that there is a fault in the air bag Supplemental Restraint System (SRS) .
The air bag Restrain Control Module (RCM) module monitors the air bag indicator for open and short to ground conditions. If the ECS detects an open or short to battery condition on the air bag indicator circuit, it will store a Diagnostic Trouble Code (DTC) B1870 in memory.
If the RCM detects an air bag indicator failure in addition to another SRS failure, the RCM will send a signal to the Generic Electronic Module (GEM) module to produce five sets of five tone bursts.