Supplemental Inflatable Restraint (SIR)

CIRCUIT DESCRIPTION

The inflatable restraint Sensing and Diagnostic and Seat Belt Pretensioner Module (SDM) performs tests to diagnose critical malfunctions within itself when the ignition switch is turned ON. The SDM monitors the firing loops to detect leakage currents to ground and system voltage in the air bag inflator module and seat belt pretensioner circuits. The deployment loop resistances are measured to ensure they are within their respective normal resistance ranges. The SDM then goes into a Continuous Monitoring mode. The SDM service wait time is 1 minute. Refer to Air Bag(s) Arming and Disarming.

CONDITIONS FOR SETTING THE DTC

The SDM is installed in the vehicle in an unconfigured state. A replacement SDM must be programmed by the technician using a scan tool. This malfunction is detected asynchronously when the IGNITION voltage is above a specified value.


ACTION TAKEN WHEN THE DTC SETS

^ The SDM sets a diagnostic trouble code.

^ The SDM turns ON the AIR BAG warning lamp.


CONDITIONS FOR CLEARING THE DTC

The Serial Data configuration programming via the scan tool is successful.


TEST DESCRIPTION

An example test description follows:

2. This step checks the status of the SIR system programming configuration.