Chart A-1

Chart A-1:

DERM Circuit:

DESCRIPTION:

When the Ignition Switch is first turned "ON" system voltage is applied through fuse #1 (#14 Toronado) to "SIR Indicator High" (B9) and to the "INFLATABLE RESTRAINT indicator Lamp which is connected to "SIR Indicator Low" (A1). Fuse #14 (#9 Toronado) 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.

NOTES ON FAULT TREE:

1. The DERM determines that the Arming Sensor is closed When system voltage or more is present at the "Sense Hi" input, and it determines that a Discriminating sensor in closed when it notes low voltage at the "Sense Low" input. There are some faults that may "look" like an accident to the DERM, and therefore record a Code 51. History Code 51 therefore is not proof that the vehicle was in an accident.

2. If a history Code 51 is set, history code 34 will not set. Therefore, any conditions which will cause a current code 34 to set will not set a history code 34 if a history Code 51 is set. If the "INFLATABLE RESTRAINT" indicator alerts the owner intermittently of a current code and no corresponding history codes are set, the most likely cause is an intermittent open in CKT 1139.

3. Checks for intermittent electrical conditions within the steering column.

4. Checks for intermittent shorts in the 36VLR wiring (CKT 236).

5. Checks for burned or mis-installed fuse #15 and "INFLATABLE RESTRAINT" indicator bulb or uncleared code 61 after a completed wiring repair on CKT 139. Also checks for intermittent faults in CKTs 688 and 358.

6. Checks for intermittent opens in the ground path of the deployment loop between the base of the steering column and both discriminating sensors (CKTs 349 and 1003).