DTC 22 - Driver Initiator Circuit Resistance Low: Description

When the ignition is turned ON, the SDM will perform tests to diagnose critical malfunction within itself. Upon passing these tests Ignition 1, 36 VLR and deployment loop voltages are measure to ensure they are within normal voltage ranges. The SDM then proceeds with the "Current Source Diagnostics". "Driver Side LO" terminal A2 is grounded through a resistor and driver current source connected to "Driver Side HI" terminal A1 allows a known amount of current to flow. By monitoring the voltage difference between "Driver Side HI" and "Driver Side LO" the SDM calculates the combined resistance of the driver inflator module, SIR coil assembly, harness wiring circuits 347 and 348 and connector terminal contact.