U code network Medium severity

U1953 U1953: "Module Communication Failure

The OBD2 code U1953 indicates a "Module Communication Failure," meaning there is a problem with communication between vehicle modules, often due to a fault in the wiring, connectors, or the modules themselves

Definition

The OBD2 code U1953 indicates a "Module Communication Failure," meaning there is a problem with communication between vehicle modules, often due to a fault in the wiring, connectors, or the modules themselves

Common causes

  • Faulty wiring or connectors
  • Failed or malfunctioning control module
  • Corrupted software or firmware in the module
  • Poor ground connections
  • Intermittent electrical issues
  • Communication network issues (e.g., CAN bus problems)
  • Low battery voltage or power supply issues
  • Damaged or corroded pins in connectors
  • Incompatible or missing modules in the network

Common misdiagnoses

  • Faulty wiring or connectors
  • Defective control module
  • Software issues or updates needed
  • Battery or power supply problems
  • Grounding issues
  • Intermittent communication issues
  • Other communication protocol failures

Troubleshooting steps

  1. 1. Check for Other Codes

    Use an OBD-II scanner to check for any other trouble codes that may be present. Sometimes, multiple codes can provide more context for the issue

  2. 2. Inspect Wiring and Connectors

  3. 3. Visually inspect the wiring and connectors associated with the affected module(s). Look for signs of damage, corrosion, or loose connections

  4. 4. Pay special attention to the ground connections, as poor grounding can lead to communication issues

  5. 5. Check Power Supply

    Ensure that the affected module is receiving the proper voltage and ground. Use a multimeter to check the power and ground circuits

  6. 6. Test the Module

    If possible, test the affected module to ensure it is functioning correctly. This may involve bench testing or swapping with a known good module

  7. 7. Check for Intermittent Issues

    Sometimes, communication failures can be intermittent. Wiggle the wiring harnesses and connectors while monitoring the communication to see if the issue can be replicated

  8. 8. Inspect the CAN Bus

    If the vehicle uses a Controller Area Network (CAN) bus for communication, check the integrity of the CAN bus wiring. Look for shorts, opens, or high resistance in the bus lines

  9. 9. Scan for Communication Issues

    Use a professional-grade scan tool to monitor the communication between modules. This can help identify which module is not communicating properly

  10. 10. Update Software/Firmware

    In some cases, a software update for the vehicle's modules may resolve communication issues. Check with the manufacturer for any available updates

  11. 11. Reset the Modules

    Sometimes, resetting the modules by disconnecting the battery for a few minutes can clear temporary communication issues

  12. 12. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to the specific make and model of the vehicle. Manufacturers may have issued guidance on common communication issues. 1

  13. 13. Professional Diagnosis

    If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership with experience in diagnosing communication issues. By following these steps, you can systematically identify and resolve the underlying cause of the U1953 code