Operation CHARM: Car repair manuals for everyone.

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 fuse 9 to "Redundant Indicator Ignition 1," terminal "B2", and to the "AIR BAG" warning lamp which is connected to "SIR Indicator," terminal "B1". Fuse 3 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 "AIR BAG" 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. This test checks whether the malfunction is due to an open "AIR BAG" 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" fuse.
4. This test checks whether the "AIR BAG" fuse is a 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.