Chart B Air Bag Warning Lamp Comes on Steady

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION

When the ignition switch is first turned "ON," "Ignition 1" voltage is applied from the "IGN(RUN/CRNK)CHIME CLSTR #1D" fuse to "Redundant Indicator Ignition 1," terminal "A4," and to the "AIR BAG" warning lamp which is connected to "SIR Indicator," terminal "A9." The "AIRBAG #1C" fuse applies system voltage to the "Ignition 1" input, terminal "B9." The SDM responds by flashing 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. When the engine is being cranked, "Ignition 1" voltage is applied from the "CRNK AIRBAG/VATS #1A" fuse to the SDM at the "Crank" input. The SDM 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 SDM will flash the "AIR BAG" warning lamp six times.

CHART TEST DESCRIPTION

Numbers below refer to circled numbers on the diagnostic chart.

1. An open "AIRBAG #1C" fuse would cause the "AIR BAG" warning lamp to come "ON" steady.

2. A disconnected SDM harness connector will cause the warning lamp to come "ON" steady via the shorting bar from terminal "A9" to terminal "A10" (ground).

3. This test checks for an open in the ground circuit to the SDM.

4. This test checks for an open in the "Ignition 1" circuit to the SDM.

5. This test checks for a short from the "Crank" input circuit to B+.

6. This test checks for a short from the "SIR Indicator" circuit to ground.

7. This test checks whether a short to ground caused the "AIRBAG #1C" fuse to open.

8. This test determines whether the short to ground is due to a short in the wiring.