Circuit Description
The electronic brake control module (EBCM) monitors the steering wheel position sensor signal for vehicle stability control (VSC) system operation.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC C1231 Steering Position Sensor Circuit Malfunction
Conditions for Running the DTC
DTC C1231 can be set anytime the ignition is in the ON position.
Conditions for Setting the DTC
The EBCM does not receive data from the steering wheel position sensor.
Action Taken When the DTC Sets
| • | The traction control and VSC is disabled. |
| • | The VSC warning indicator turns ON. |
Conditions for Clearing the DTC
The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
Diagnostic Aids
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:
| • | An open, high resistance, or short to ground in the steering wheel position sensor ignition positive voltage circuits |
| • | An internal steering wheel position sensor malfunction |
If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 | Is U0073, U0123, U0124, or U0126 also set? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC information | Go to Step 3 |
Does the voltage measure as specified? | 10-14 V | Go to Step 5 | Go to Step 4 | |
4 | Locate and repair an open, high resistance, or short to ground in the ignition positive voltage circuits of the steering wheel position sensor. Did you find and correct the condition? | -- | Go to Step 6 | -- |
5 | Replace the steering wheel position sensor. Refer to Steering Wheel Position Sensor Replacement . Did you complete the replacement? | -- | Go to Step 6 | -- |
6 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
