Resistor Module
WARNING: This page is about a different car, the 1991 Oldsmobile Custom Cruiser, 1991 Chevrolet Caprice, and 1991 Buick Roadmaster. However, it is still accessible from the selected car via links, so may be relevant.
The resistor module is located in the SIR harness between the inflator module and the Diagnostic Energy Reserve Module (DERM). The resistor module allows the DERM to monitor the deployment loop for faults and to detect when a deployment has occurred.
The resistors in the resistor module are balanced with the resistors on the arming and discriminating sensors to allow the DERM to monitor the voltage drops across the components of the deployment loop. Faults are detected during normal non-deployment conditions by monitoring these voltages. On some vehicles, the resistor module is mounted on the DERM.