Part 1 of 2

Test C: Inflatable Restraint Warning Lamp Does Not Come ON (Part 1 Of 2):

Supplemental Inflatable Restraint (SIR):

OPERATION:
When the ignition switch is first turned "ON," "Ignition 1" voltage is applied from the "IGN" fuse 1D to "Redundant Indicator Ignition 1," terminal "B2" and to the INFLATABLE RESTRAINT" warning lamp which is connected to "SIR Indicator," terminal "B1." The "AIR BAG" fuse 1C applies system voltage to the "Ignition 1" inputs, terminals "A9" and "A10." The DERM responds by flashing the "INFLATABLE RESTRAINT" warning lamp 7 times.

When the engine is being cranked, "Ignition 1" voltage is applied from the "CRANK" fuse 1A 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 "INFLATABLE RESTRAINT" warning lamp being "ON" during cranking.

After cranking, the DERM will flash the "INFLATABLE RESTRAINT" warning lamp 6 times.

POSSIBLE CAUSES:
Test Description: Number(S) below refer to circled number(S) on the diagnostic chart.
1. This test determines whether the malfunction is in the DERM circuitry or in the instrument cluster power feed circuitry.
2. This test confirms the integrity of the "Redundant Indicator Ignition 1" circuit.
3. This test checks for an open in the "SIR Indicator" circuit, Instrument cluster circuitry, and "INFLATABLE RESTRAINT" warning lamp bulb.
4. This test checks whether the open is due to a bad bulb.
5. This test determines whether the malfunction is an open in the "SIR Indicator" circuit or an open in the instrument cluster.
6. This test determines whether the malfunction is a short from the "SIR Indicator" circuit to B+ or a malfunctioning DERM.