WOMS
U code network Medium severity

U020D Lost Communication with Seat Control Module

The OBD2 code U020D indicates a loss of communication with the seat control module, meaning the vehicle's computer is unable to communicate with the module responsible for controlling the seat functions

Definition

The OBD2 code U020D indicates a loss of communication with the seat control module, meaning the vehicle's computer is unable to communicate with the module responsible for controlling the seat functions

Common causes

  • Faulty seat control module
  • Damaged wiring or connectors
  • Corroded terminals
  • Poor ground connection
  • Faulty body control module (BCM)
  • Software issues or glitches
  • Low battery voltage
  • Intermittent electrical connections

Common misdiagnoses

  • Faulty Seat Control Module
  • Wiring issues or shorts in the harness
  • Faulty Body Control Module (BCM)
  • Issues with the Powertrain Control Module (PCM)
  • Faulty connectors or terminals
  • Battery or power supply problems
  • Software or firmware issues in the modules
  • Faulty CAN bus communication lines

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 related to the seat control module 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. Check Power and Ground

    Power Supply: Verify that the seat control module is receiving the correct voltage. Use a multimeter to check the power supply at the module

  5. 5. Ground Connection

    Ensure that the ground connection for the seat control module is secure and functioning properly

  6. 6. Inspect the Seat Control Module

    Module Condition: Check the seat control module for any physical damage or signs of water intrusion

  7. 7. Reprogramming

    If applicable, consider reprogramming or updating the software of the seat control module

  8. 8. Test Communication

    CAN Bus Check: Use a scan tool to check the communication on the CAN bus. If other modules are not communicating, there may be a broader issue with the network

  9. 9. Module Functionality

    If possible, test the seat control module in another vehicle to confirm it is functioning correctly

  10. 10. Check for Intermittent Issues

    Wiggle Test: While monitoring the communication with a scan tool, perform a wiggle test on the wiring harness to see if the communication is restored, indicating a possible intermittent connection issue

  11. 11. Inspect Related Components

    Other Modules: Check other related modules (like the Body Control Module) for communication issues, as they may affect the seat control module

  12. 12. Fuses

    Inspect fuses related to the seat control system to ensure they are not blown

  13. 13. Clear Codes and Test Drive

    After performing the above checks and repairs, clear the trouble codes and take the vehicle for a test drive to see if the code returns

  14. 14. Consult Technical Service Bulletins (TSBs)

    Look for any TSBs related to the seat control module for your specific vehicle make and model, as there may be known issues or recalls

  15. 15. Seek Professional Help

    If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or dealership for further diagnosis. By following these steps, you should be able to identify the root cause of the U020D code and take appropriate action to resolve the communication issue with the seat control module