Chart D

Chart D:

DERM Circuit Detail:

DESCRIPTION:

When the Ignition Switch is first turned "ON" system voltage is applied through fuse #15 to "SIR Indicator High' (B9) and to the "INFLATABLE RESTRAINT' Indicator Lamp which is connected to "SIR Indicator Low" (A1). Fuse #12 also applies system voltage to the "IGNITION 1" inputs (A3 and B3). The DERM responds by blinking the "INFLATABLE RESTRAINT" indicator 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 lamp circuit until system voltage is removed from the "CRANK" input. This results in a steady "INFLATABLE RESTRAINT" indicator during cranking.

After cranking the DERM will again blink the "INFLATABLE RESTRAINT" indicator 7 to 9 times if the Ignition Switch is "ON".

NOTES ON FAULT TREE:

1. Checks for blown fuse #11 which supplies "CRANK" input of the DERM during cranking.

2. Checks for short to voltage on circuit 806 (between fuse #11 and DERM).

3. Checks for short to ground on circuit 806.

4. Determines if DERM has an internal fault causing fuse #11 to blow.