Chart D Air Bag Warn Lamp Does Not Come ON Steady During Crank

Diagnostic Chart:

Electrical Diagram:

CIRCUIT DESCRIPTION
When the ignition switch is first turned "ON." "Ignition 1" voltage is applied from the "CHIME/CLSTR/RAC/MISC #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 "AIR BAG/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
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test checks whether the malfunction is due to an open "AIR BAG/VATS #1A" fuse.
2. This test checks for a proper signal to the "Crank" input during cranking.
3. This test determines whether the lack of a proper crank signal is due to an open "Crank" input circuit or an open power feed to the "AIR BAG/VATS #1A" fuse.
4. This test checks whether the "AIR BAG/VATS #1A" fuse is open due to a short to ground in the "Crank" input circuit.
5. This test determines whether the short to ground is in the wiring harness.