Chart C Air Bag Warning Lamp Does Not Comes ON

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION
When the ignition switch is first turned "ON, "Ignition 1" voltage is applied from the "GAGES" fuse to "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" inputs, terminals "A9" and "A10." The DERM responds by flashing the "AIR BAG" warning lamp 7 times.

When the engine is being cranked, "Ignition 1" voltage is applied from the "CRANK" fuse to the DERM at the "Crank" input. The DERM responds by grounding the "SIR Indicator" Output until "Ignition 1" voltage is removed from the "Crank" input. This results in the "AIR BAG" warning lamp being "ON" during cranking.

After cranking, the DERM will flash the "AIR BAG" warning lamp 6 times.

TABLE TEST DESCRIPTION
Number(s) below refer to step number(s) on the diagnostic table.
1. The "SIR DIAGN0STlC SYSTEM CHECK" should be the starting point for all diagnosis. SIR Diagnostic System Check
2. This test determines whether the malfunction is in the DERM circuitry or in the instrument cluster power feed circuitry.
3. Refer to note at top of table.
5. Refer to note at top of table.
6. Refer to note at top of table.
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+.
12. Refer to note at top of table.
14. Refer to note at top of table.
16. This test checks whether the open is 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.
21. This test checks whether power is available to the instrument cluster power feed circuit.
22. This test checks for a short from the instrument cluster power feed circuit to ground.
24. This test determines whether the short to ground is due to a short in the wiring or a malfunctioning DERM.
26. Refer to note at top of table.
28. Refer to note at top of table.
30. This test determines whether the malfunction is due to an open power feed circuit from the "GAGES" fuse to the instrument cluster or an open power feed to the "GAGES" fuse.