Air Bag Warning Lamp Does Not Come On

When measurements are requested in this chart use J 39200 Digital Multimeter with correct terminal adapter from J 35616-A Connector Test Adapter Kit. When a check for proper connection is requested, refer to Intermittents and Poor Connections in Diagrams. When a wire, connector or terminal repair is requested, use J 38125-A Terminal Repair Kit and refer to Wiring Repair.

CIRCUIT DESCRIPTION
When you first turn the ignition switch ON, the GAUGES fuse applies Ignition 1 voltage to the Redundant Indicator Ignition 1, terminal B2, and to the AIR BAG warning lamp which is connected to SIR Indicator terminal B1. The AIR BAG fuse applies system voltage to the Ignition 1 input terminals A9 and A10. The inflatable restraint Diagnostic Energy Reserve Module (DERM) then flashes the AIR BAG warning lamp seven times. If Ignition 1 is outside of the normal operating voltage range, the AIR BAG warning lamp will come on solid with no DTCs set. During engine cranking, the CRANK fuse applies Ignition 1 voltage to the DERM at the Crank input. The DERM then grounds the SIR Indicator output until Ignition 1 voltage is removed from the Crank input. The AIR BAG warning lamp being then comes on during cranking.
After cranking, the DERM flashes the AIR BAG warning lamp six times.

TEST DESCRIPTION
Refer to step numbers on the diagnostic table.
1. Start at the SIR Diagnostic System Check for all diagnosis.
2. This test determines whether the malfunction is in the DERM circuitry or in the instrument cluster power feed circuitry.
8. This test checks for an open in the SIR Indicator circuit, instrument cluster circuitry, and AIR BAG warning lamp bulb.
9. This test determines whether the malfunction is a short from the SIR Indicator circuit to B+.
16. This test checks for an open condition due to a bad bulb.
18. This test determines whether the malfunction is an open in the SIR Indicator circuit or an open in the instrument cluster.
22. This test determines where the open in circuit 358 is located.
26. This test will determine if the blown fuse was the result of fatigue or a circuit short.
28. This test determines whether the short-to-ground is due to a short in the wiring or a malfunctioning DERM.
34. This test checks for malfunctions due to the following conditions:
^ An open power feed circuit from the GAUGES fuse to the instrument cluster.
^ An open power feed to the GAUGES fuse.