Chart B 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 "GAGES" fuse to "Redundant Indicator Ignition 1," terminal "B2," and to the "AIR BAG" warning lamp which is connected to "SIR Indicator," terminal "B 1." 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. 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 "SIR CRANK SENSE" 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.

CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. An open "AIR BAG" fuse would cause the "AIR BAG" warning lamp to come "ON" steady.
2. A disconnected DERM harness connector will cause the warning lamp to come "ON" steady via the shorting bar from terminal "A1" to terminal
3. This test checks for an open in the "Ignition 1" circuitry to the DERM.
4. This test checks for a short from the "SIR Indicator" circuit to ground.
5. This test checks for a short from the "Crank" input circuit to B+.
6. This test checks whether a short to ground caused "AIR BAG" fuse to open.
7. This test determines whether the short to ground is due to a malfunctioning arming sensor or a short in the wiring.