Diagnostic Aids

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If Ignition 1 voltage is outside of the normal operating voltage range (9-16 volts), the AIR BAG warning lamp will come ON solid with no DTCs set.
The loss of serial data communication between the inflatable restraint sensing and diagnostic module (SDM) and the instrument panel cluster (IPC), will cause the AIR BAG warning lamp to come ON solid. Refer to DTC U1001-U1254 in Data Link Communications.