WOMS
C code chassis Medium severity

C1231 Speed Wheel Sensor Rear Center Circuit Open

The OBD2 code C1231 indicates that there is an open circuit in the rear center speed wheel sensor, which means the vehicle's system is not receiving a signal from that sensor, potentially affecting traction control and...

Definition

The OBD2 code C1231 indicates that there is an open circuit in the rear center speed wheel sensor, which means the vehicle's system is not receiving a signal from that sensor, potentially affecting traction control and stability systems

Common causes

  • Faulty speed wheel sensor
  • Damaged wiring or connectors
  • Poor electrical connections
  • Corroded terminals
  • Open circuit in the wiring harness
  • Faulty ABS control module
  • Incorrectly installed or misaligned sensor

Common misdiagnoses

  • Faulty wheel speed sensor
  • Damaged wiring or connectors
  • ABS control module failure
  • Incorrectly installed or misaligned sensor
  • Brake system issues
  • Faulty vehicle speed sensor
  • Problems with the ABS tone ring

Troubleshooting steps

  1. 1. Visual Inspection

    Wiring and Connectors: Inspect the wiring harness and connectors associated with the rear center wheel speed sensor. Look for any signs of damage, fraying, corrosion, or loose connections

  2. 2. Sensor Condition

    Check the condition of the wheel speed sensor itself. Ensure it is securely mounted and not damaged

  3. 3. Check for Other Codes

    Use an OBD-II scanner to check for any additional trouble codes that may provide more context or indicate related issues

  4. 4. Test the Wheel Speed Sensor

    Resistance Test: Disconnect the wheel speed sensor and use a multimeter to measure the resistance across the sensor terminals. Compare the reading to the manufacturer's specifications

  5. 5. Signal Test

    If applicable, use an oscilloscope or a multimeter set to measure AC voltage to check for a signal while the wheel is being turned. This can help determine if the sensor is functioning properly

  6. 6. Inspect the Circuit

    Continuity Test: With the sensor disconnected, perform a continuity test on the wiring from the sensor connector to the vehicle's control module. Look for any breaks or shorts in the wiring

  7. 7. Voltage Test

    Check for proper voltage at the sensor connector with the ignition on. Ensure that the sensor is receiving the correct voltage as specified by the manufacturer

  8. 8. Check the Control Module

    If the sensor and wiring are in good condition, the issue may lie within the vehicle's control module. Check for any software updates or known issues with the module

  9. 9. Clear Codes and Test Drive

    After performing repairs or adjustments, clear the trouble codes using the OBD-II scanner and take the vehicle for a test drive to see if the code returns

  10. 10. Seek Professional Help

    If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician who has access to advanced diagnostic tools and equipment. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the C1231 code