Storm L4-1800cc 1.8L DOHC (1993)
Standby Power Supply: Description and Operation
The DERM is designed to perform the following functions in the SIR system:
1.
Energy reserve: The DERM maintains a 36 volt loop reserve (36VLR) energy supply to provide deployment energy for a few seconds if the
vehicle voltage is low or if lost in a vehicle accident.
2.
Malfunction detection: The DERM performs diagnostic monitoring of SIR system electrical components.
3.
Malfunction recording: The DERM provides SIR system fault code information through a SCAN/TECH tool or the SIR warning lamp.
4.
Driver Notification: The DERM warns the driver of SIR system faults by controlling the SIR warning lamp.
5.
Accident recording: The DERM records the SIR system status during a vehicle accident.
The DERM is connected to the SIR harness by a 24-way connector. This harness connector utilizes a shorting bar across certain terminals in the
contact area. This shorting bar connects the SIR warning lamp output to ground when the DERM connector is disconnected. This will cause the lamp to
illuminate steady whenever the ignition switch is at the Run, Bulb Test, or Start positions with the DERM disconnected.
