Yukon/Denali 4WD V8-5.3L VIN T (2004)
Air Bag Deactivation Indicator: Description and Operation
AIR BAG INDICATOR
The AIR BAG indicator, located on the instrument panel cluster (IPC) is used to notify the driver of SIR system malfunctions and to verify that the SDM
is communicating with the IPC. When the ignition is turned ON, the SDM is supplied with ignition 1 voltage and requests the IPC to flash the AIR BAG
indicator 7 times. While flashing the indicator, the SDM conducts test on all SIR system components and circuits. If no malfunctions are detected the
SDM will communicate with the IPC through the class 2 serial data circuit and request the IPC to turn the AIR BAG indicator OFF. The SDM provides
continuous monitoring of the air bag circuits by conducting a sequence of checks. If a malfunction is detected the SDM will store a diagnostic trouble
code (DTC) and request the IPC to turn the AIR BAG indicator ON. The presence of a SIR system malfunction could result in non-deployment of the air
bags. The AIR BAG indicator will remain ON until the malfunction has been repaired.
