Operation CHARM: Car repair manuals for everyone.

Passenger Compartment Sensor

WARNING: The diagnostic energy reserve module or sensing and diagnostic module (DERM/SDM) can maintain enough voltage to cause air bag deployment for up to two minutes after the ignition switch is turned off and the battery is disconnected. Servicing the SIR system during this period may result in accidental deployment and personal injury.


1. Disarm system as described in Air Bag System Disarming & Arming.
2. Remove instrument panel end caps, then the glove compartment trim strip.
3. Remove radio and HVAC control trim plate.
4. Remove instrument panel top pad.
5. Remove Connector Position Assurance (CPA), then disconnect DERM electrical connector.
6. Remove DERM attaching bolts, then the DERM from vehicle.
7. Remove Connector Position Assurance (CPA), then disconnect sensor electrical connector.
8. Remove sensor attaching bolts, then the sensor from vehicle.
9. Reverse procedure to install, noting the following:
a. Install sensor with arrow pointed toward front of vehicle.
b. After completing installation, rearm system as described in Air Bag System Disarming & Arming.
c. Turn ignition switch on and verify that the AIR BAG or SIR warning lamp flashes seven to nine times and then turns off. If lamp does not respond as specified, refer to System Diagnosis.