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

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION

When the ignition switch is first turned "ON," "Ignition 1" voltage is applied from the "RLY IGN 1" fuse to "Redundant Indicator Ignition 1," terminal "A4," and to the "AIR BAG" warning lamp which is connected to "SIR Indicator," terminal "A9." The "SIR" 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 "CRANK" 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. This test checks whether the malfunction is due to an open "CRANK" 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 "CRANK" fuse.

4. This test checks whether the "CRANK" 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.