WOMS
U code network Medium severity

U2138 Lost Communication with the Steering Angle Sensor

The OBD2 code U2138 indicates that there is a loss of communication between the vehicle's control module and the steering angle sensor, which may affect systems that rely on steering input for operation

Definition

The OBD2 code U2138 indicates that there is a loss of communication between the vehicle's control module and the steering angle sensor, which may affect systems that rely on steering input for operation

Common causes

  • Faulty steering angle sensor
  • Damaged wiring or connectors
  • Poor electrical connections
  • Malfunctioning control module
  • Software issues or updates needed
  • Corrosion or dirt in connectors
  • Battery or power supply issues
  • Faulty CAN bus communication

Common misdiagnoses

  • Faulty Steering Angle Sensor
  • Wiring Issues or Short Circuits
  • Faulty Body Control Module (BCM)
  • Faulty Electronic Power Steering (EPS) Module
  • Incorrectly Calibrated Steering Angle Sensor
  • Faulty Instrument Cluster
  • Issues with the CAN Bus Communication
  • Battery or Power Supply Problems

Troubleshooting steps

  1. 1. Check for Other Codes

    Use an OBD-II scanner to check for any additional trouble codes. Sometimes, multiple codes can provide more context about the issue

  2. 2. Inspect Wiring and Connectors

    Visual Inspection: Check the wiring harness and connectors associated with the steering angle sensor for any signs of damage, corrosion, or loose connections

  3. 3. Connector Pins

    Ensure that the pins in the connectors are not bent, corroded, or pushed back

  4. 4. Test the Steering Angle Sensor

    Sensor Functionality: If possible, test the steering angle sensor using a multimeter or scan tool to ensure it is functioning correctly. Check the output voltage or resistance as specified in the vehicle’s service manual

  5. 5. Calibration

    Some vehicles require the steering angle sensor to be calibrated after installation or repair. Check if calibration is necessary

  6. 6. Check Power and Ground

    Power Supply: Verify that the steering angle sensor is receiving the correct voltage. Use a multimeter to check the power supply at the sensor connector

  7. 7. Ground Connection

    Ensure that the ground connection for the sensor is intact and providing a good ground

  8. 8. Inspect the CAN Bus

    Communication Lines: Since the steering angle sensor communicates over the CAN bus, check for any issues with the CAN wiring. Look for shorts, opens, or interference in the communication lines

  9. 9. Other Modules

    Ensure that other modules on the CAN bus are functioning correctly, as a fault in another module can affect communication

  10. 10. Check for Software Updates

    ECU Updates: Check if there are any software updates available for the vehicle’s ECU that may address communication issues

  11. 11. Clear Codes and Test Drive

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

  12. 12. Professional Diagnosis

    If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership, as they may have specialized tools and knowledge to diagnose the problem further. By following these steps, you should be able to identify the cause of the U2138 code and take appropriate action to resolve the communication issue with the steering angle sensor