When the ignition switch is turned to ON, the sensing and diagnostic module (SDM) will perform a turn-on test to diagnose critical malfunctions within the SDM itself.
Upon passing this test, ignition and deployment loop voltages are measured to ensure that they are within their normal voltage ranges. The SDM monitors the voltages at the driver low and the passenger low to detect shorts to ground or voltage in the deployment loops.
This diagnostic procedure supports the following DTC:
DTC 004 Driver Air Bag Deployment Loop Short To Voltage
Ignition voltage is within the normal operating voltage range.
• | The air bag wiring of the driver high is shorted to battery wiring. |
• | The air bag wiring of the driver low is shorted to battery wiring. |
The SDM commands the AIR BAG indicator ON.
The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
Step | Action | Values | Yes | No |
---|---|---|---|---|
Warning: Refer to Sensing and Diagnostic Module Voltage after Ignition is Turned Off Warning in the Preface section. Warning: Refer to Sensing and Diagnostic Module Handling Warning in the Preface section. Schematic Reference: SIR Schematics Connector End View Reference: Component Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | ||
2 | Visually inspect the supplemental inflatable restraints (SIR) harness for damage. Is there any visible damage to the SIR harness? | -- | Go to Step 3 | Go to Step 4 |
3 | Replace the SIR wiring harness. Did you complete the repair? | -- | Go to Step 9 | -- |
4 |
The shorting bar at the disconnected SDM connector will create a complete circuit between the wires from the steering wheel module. Does the voltage measure greater than the specified value? | 0 V | Go to Step 7 | Go to Step 5 |
5 |
Is DTC 004 still shown as a current fault? | -- | Go to Step 6 | Go to Step 9 |
6 | Replace the steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement. Did you complete the repair? | -- | Go to Step 9 | -- |
7 |
The shorting bar at the disconnected SDM connector will create a complete circuit between the wires from the steering wheel module coil. Is the voltage equal to the specified value? | 0 V | Go to Step 8 | Go to Step 3 |
8 | Replace the steering wheel module coil. Refer to Inflatable Restraint Steering Wheel Module Coil Replacement. Did you complete the repair? | -- | Go to Step 9 | -- |
9 |
Does the DTC reset? | -- | Go to Step 2 | System OK |