DTC 04

Circuit Description
When the ignition switch is turned ON, the Sensing and Diagnostic Module (SDM) will perform tests to diagnose any malfunctions within itself. If a failure is not detected by the internal tests, the SDM will test the driver airbag module firing circuit. The SDM allows a very small amount of current to flow through the circuit. The SDM monitors voltage during this test.

DTC 04 Will Set When
The firing circuit is shorted to voltage.

CAUTION: Before replacing components, disconnect the negative battery cable. Wait one minute for the SDM capacitor to discharge. The capacitor supplies reserve power to deploy the airbags, even if the battery is disconnected. Unintentional deployment of the airbags can cause injury.

Steps 1 - 7:

DTC 04 - Driver Firing Circuit, Short To Battery Voltage