Chart A Intermittent DTC Diagnosis

CIRCUIT DESCRIPTION
When system voltage is applied to the center sensor assembly. It will perform the "Primary Check" followed by the "Constant Check." When a fault is detected, the center sensor assembly will store a DTC and illuminate the air bag indicator. When a DTC is stored, the safety circuit (inside the center sensor assembly) will open, preventing SRS operation. All faults must be repaired and all DTCs must be cleared before the safety circuit closes, allowing the SRS to function normally.

TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. Checks for intermittent shorts to ground in the steering column and forward sensor circuits. Also checks for intermittent shorts from the high side of the forward sensor circuits to the low side.
2. Checks for intermittent shorts to B+ in the steering column and forward sensor circuits. Also checks for intermittents opens in both forward sensor circuits.
3. Checks for intermittent shorts from the high side of the steering column circuit to the low side.
4. Checks for intermittent opens in the steering column circuit.
5. Checks for intermittent conditions within the steering column.
6. Checks for intermittent opens in one of the forward sensor circuits.
7. A DTC 22 will set if the instrument cluster is disconnected or removed and the ignition switch is turned to "ACC" or "ON."
8. Checks for open ECU-B fuse or air bag indicator bulb. Also checks for intermittent opens and shorts to ground in the air bag indicator circuits.