Chart 2

Code 25 (Chart 2):

DERM Circuit Detail:

DESCRIPTION:

The DERM grounds the Force Low input (terminal A10) and then monitors the voltage at the Sense Low input (terminal A6). If the voltage is greater than 3 volts Code 25 will set. Code 25 is an indication of a short to system voltage in the steering column, Dual Sensor, or associated wiring. Additionally, this code can be set if the actual resistance of the 100 ohm resistor within the Resistor Module is too high or is open.

TEST CONDITIONS:

Tested once each ignition cycle during the "Steering Column Resistance Test" if:
1. No faults are detected during "Turn-on".
2. No faults are detected during "Continuous Monitoring" for 1 second.
3. No Crank signal present.

FAILURE CONDITIONS:

Code 25 will set if the voltage at the Sense Low Input (terminal A6) is equal to "IGNITION 1" voltage (+/- 2 volts) during the first portion of the Steering Column Resistance Test.

CONDITIONS TO CLEAR:

Current Code 25 will be cleared each time the Ignition Switch is turned OFF.

ACTION TAKEN:

DERM turns on the "INFLATABLE RESTRAINT" indicator lamp.

NOTES ON FAULT TREE:

1. Checks if fault is present on low side of the Steering Column circuits or in the circuits between the DERM and Resistor Module.

2. Checks if fault is a short to voltage on CKTs 348A or 348B.

3. Checks if fault is in the Dual Sensor.

4. Determines if fault is in the Forward Sensor or in CKT 349.