The steering wheel module deployment loop consists of an inflatable restraint steering wheel module, an inflatable restraint steering wheel module coil, the steering wheel module - high and steering wheel module - low circuits. A shorting bar is used in the inflatable restraint steering wheel module and the inflatable restraint steering wheel module coil connectors which will short together the steering wheel module - high and steering wheel module - low circuits when the connector is disconnected, this will help to prevent unwanted deployment of the inflator module during servicing. During a frontal crash of sufficient force the SDM will allow current to flow through the deployment loop in order to deploy the inflatable restraint steering wheel module. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a DTC will be stored.
Ignition 1 Voltage is within the normal operating voltage range.
The DTC will set if one of the following conditions occurs:
• | The steering wheel module high input is more than 6 volts for 500 milliseconds. |
• | The steering wheel module high input is less than 2 volts and steering wheel module deployment loop resistance is less than 4.5 ohms for 500 milliseconds. |
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. |
• | A history DTC will clear once 250 malfunction free ignition cycles have occurred. |
Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.
The following are possible causes of the malfunction:
• | A short to ground in the steering wheel module high or the steering wheel module low circuit. |
• | A short to voltage in the steering wheel module high or the steering wheel module low circuit. |
• | A malfunctioning inflatable restraint steering wheel module. |
• | A malfunctioning inflatable restraint steering wheel module coil. |
• | An internal SDM malfunction. |
If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
The number(s) below refer to the step number(s) on the diagnostic table.
Tests to see if the malfunction is intermittent.
Tests to see if the malfunction is caused by either the inflatable restraint steering wheel module or steering wheel module coil.
Determines whether the malfunction is caused by the steering wheel module or the steering wheel module coil.
Tests for a short to ground or a short to voltage in the Steering Wheel Module High and Steering Wheel Module Low circuits.
Step | Action | Yes | No |
---|---|---|---|
Schematic Reference: SIR Schematics | |||
1 | Did you perform A Diagnostic System Check - SIR? | Go to Step 2 | |
2 |
Does the connector exhibit any signs of damage or corrosion? | Go to Step 3 | Go to Step 4 |
3 |
Did you complete the repair? | Go to Step 12 | -- |
Does the scan tool indicate that DTC B1024 is current? | Go to Step 5 | Go to Diagnostic Aids | |
Does the scan tool indicate that DTC B1024 is current? | Go to Step 9 | Go to Step 6 | |
Does the scan tool indicate that DTC B1024 is current? | Go to Step 7 | Go to Step 8 | |
7 |
Did you complete the replacement? | Go to Step 12 | -- |
8 |
Did you complete the replacement? | Go to Step 12 | -- |
9 |
Did you find and correct the condition? | Go to Step 12 | Go to Step 10 |
Test the Steering Wheel Module - High and the Steering Wheel Module - Low circuits for a short to ground or a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 12 | Go to Step 11 | |
11 |
Did you complete the replacement? | Go to Step 12 | -- |
12 |
Does the DTC reset? | Go to Step 2 | System OK |