DTC 21 and 22

Diagnosis Chart:

Electrical Chart:

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; 4) "IGNITION 1" voltage is present.

FAILURE CONDITIONS
DTCs 21 and 22 set when the voltage at the Sense Low input (terminal A6) is less than S volts during the first portion of the steering column resistance test. This occurs when the Force Hi output (terminal A4) is open and results in an undetermined steering column resistance.

CONDITIONS TO CLEAR
Current DTCs 21 and 22 clears each time Ignition Switch is turned "OFF."

ACTION TAKEN
DERM turns on "INFLATABLE RESTRAINT" warning lamp.

DESCRIPTION
The DERM injects a 75 milliampere current through the steering column from the Force Hi output (terminal A4) to the Force Low input (terminal A10). The DERM monitors the voltage at the Sense Hi input (terminal A7) and the Sense Low input (terminal A6) and calculates the combined resistance of the Inflator Module, SIR Coil, Resistor Module, harness wiring and connector terminal contact in the steering column. DTCs 21 and 22 set when the Force Hi output (terminal A4) is open, or the Resistor Module's 100 ohm resistor is

NOTES ON FAULT TREE
1. Checks for open in Force Hi wiring.
2. Checks for open 50 ohm resistor in Resistor Module.
3. Checks for proper resistor values in Resistor Module.
4. Checks for short in Resistor Module wiring harness.
5. Checks for short in Resistor Module wiring harness.