Supplemental Inflatable Restraint (SIR)

CIRCUIT DESCRIPTION
The steering column circuit consists of the driver inflator module, SRS coil assembly, center sensor assembly and associated wires. The center sensor assembly injects a small amount of current through the steering column circuit through the D+ CKT output, terminal "B3". By monitoring the voltage at the D- CKT input, terminal "B4", the center sensor assembly calculates the combined resistance of the driver inflator module, SRS coil assembly and their associated wiring.

FAILURE CONDITIONS
DTC 14 will set if the center sensor assembly detects an open in the steering column circuit.

ACTION TAKEN
The center sensor assembly will illuminate the "AIR BAG" indicator and open the safety circuit, disabling the SRS.

TEST DESCRIPTION:
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test determines whether the fault is in the steering column components or in the SRS circuitry.
2. This test determines whether the steering column fault is due to a faulty SRS coil assembly or a faulty driver inflator module.
3. This test checks for an open in the D+ CKT.
4. This test determines whether the fault is due to an open in the D- CKT or a faulty center sensor assembly.