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AIR BAG Warning Lamp Comes On Steady















Circuit Description
When the ignition switch is first turned to the RUN position, the CHIME Fuse (Buick w/UB3) or Powertrain Control Module (PCM) Fuse (All others) applies battery voltage to the AIR BAG warning lamp that is connected to SIR Indicator terminal 7. The AIR BAG Fuse applies battery voltage to the Ignition Positive Voltage input, terminal 10. The Inflatable Restraint Sensing and Diagnostic Module (SDM) responds by flashing the AIR BAG warning lamp 7 times. If Ignition Positive Voltage is outside of the normal operating voltage range (8.2 volts - 17.1 volts), the AIR BAG warning lamp will turn ON solid with no DTCs set.

Diagnostic Aids
In order to disable the shorting bar from terminal 6 to terminal 7 inside the Inflatable Restraint Sensing and Diagnostic Module (SDM) harness connector, the following 2 conditions must be met:
^ The SDM harness connector must be properly connected to the SDM.
^ The Connector Position Assurance (CPA) must be properly installed in the SDM harness connector.

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

Test Description
The numbers below refer to the step numbers on the diagnostic table:
2. This test checks for sufficient Ignition Positive Voltage applied to the SDM.
3. This test checks for excessive Ignition Positive Voltage applied to the SDM.
4. This test checks for a properly installed CPA.
6. This test determines if the SDM is turning on the AIR BAG warning lamp.
7. This test checks for a damaged shorting bar.
9. This test determines whether the malfunction is a short to ground in circuit 358 (BRN).
10. This test checks for a short between circuit 358 (BRN) and circuit 1751 (BLK/WHT).
14. An open AIR BAG Fuse would cause the AIR BAG warning lamp to come on steady.
15. This test checks whether a short-to-ground caused the AIR BAG Fuse to open.
16. This test determines whether the short to ground is due to a short in the wiring or internal to the SDM.
20. This test checks for a disconnected SDM.
26. This test checks for an open in the Ignition Positive Voltage circuit.