The inflatable restraint sensing and diagnostic module (SDM) sends the status of the driver and passenger seat belt switch to the instrument panel cluster (IPC) via a serial data communication message. If the seat belt is unfastened, the SDM will send a message to the IPC to illuminate the fasten safety belt indicator for 72 seconds or until the seat belt is fastened.

Schematic Reference

Seat Belt Schematics

Connector End View Reference

Seat Belt Connector End Views

Electrical Information Reference

Important: When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector.

1. Turn ON the ignition. Observe the seat belt indicator on the IPC while buckling and unbuckling the malfunctioning seat belt. Also with the scan tool monitor the seat belt status parameter in the SIR scan tool data list. Verify that the seat belt indicator turns ON/OFF while the scan tool displays the seat belt is Unbuckled/Buckled.

⇒	If the scan tool displays the seat belt is unbuckled/buckled and the corresponding seat belt indicator does not turn ON/OFF, replace the IPC.

2. If the scan tool indicates that the seat belt does not perform as described, turn OFF the ignition, remove the seat belt buckle connector.

⇒	Test and repair both seat belt switch signal and ground circuit for short to ground, an open/high resistance or replace the seat belt switch.

3. Remove the SDM connector and test the seat belt switch signal and ground circuits for a short to ground, an open/high resistance.

⇒	If the circuits test good then replace the SDM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.