Diagnostic Instructions
DTC Descriptor
DTC C1231: Steering Position Sensor Circuit Malfunction
Circuit/System Description
The electronic brake control module (EBCM) monitors the steering wheel position sensor signal for vehicle stability control (VSC) system operation.
Conditions for Running the DTC
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.
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
ABS Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References
for scan tool information
Circuit/System Verification
- Verify DTC U0073, U0123, U0124, or U0126 are not set?
| ⇒ | If DTC U0073, U0123, U0124, or U0126 is set, refer to appropriate DTC. |
- Verify no speed sensor, yaw rate sensor or deceleration DTCs are set?
| ⇒ | If any speed sensor, yaw rate sensor or deceleration DTCs are set, refer to appropriate DTC prior to diagnosing C1231. |
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the EBCM.
- Test for less than 1 ohm between the terminals 1, 13 and ground.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
- Ignition ON, check for 11-14V between terminals, 12, 24, 34 and ground.
| ⇒ | If the voltage is not as specified, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the steering position sensor. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
