Chart D2 Warning Lamp Does Not Come "ON"

Diagnosis Chart:

Electrical Chart:

DESCRIPTION
When the Ignition Switch is first turned "ON" system voltage is applied through Fuse #6 to the "SIR Indicator High" input (B9) and the "INFLATABLE RESTRAINT" warning lamp which is connected to "SIR Indicator Low" input (A1). Fuse #7 also applies system voltage to the "IGNITION 1" inputs (A3 and B3). The DERM responds by blinking the "INFLATABLE RESTRAINT" warning lamp 7 to 9 times.

When the engine is being cranked, system voltage is applied to the DERM at the "CRANK" input. The DERM grounds the warning lamp circuit until system voltage is removed from the "CRANK" input. This results in a steady "INFLATABLE RESTRAINT" warning lamp during cranking.

After cranking, the DERM again blinks the "INFLATABLE RESTRAINT" warning lamp 7 to 9 times.

NOTES ON FAULT TREE
1. Determines if a short to voltage via an ignition fed source exists.
2. After the DERM is disconnected, the Shorting Bar normally supplies a ground to terminal A1 of the DERM harness. When the DERM connector from SIR Load Tool J 37808 is substituted for the DERM, the Shorting Bar which supplies the ground to terminal A1 is not allowed to close. Thus, circuit 358 is isolated from both ground and the DERM so that an accurate voltage measurement can be made.
3. Checks if DERM is defective or open circuit exists on circuit 358. Also checks for burned out warning lamp.