WOMS
U code network Medium severity

U1664 U1664: "Communication Network Malfunction

The OBD2 code U1664 indicates a communication network malfunction, meaning there is a failure in the communication between various control modules in the vehicle's network

Definition

The OBD2 code U1664 indicates a communication network malfunction, meaning there is a failure in the communication between various control modules in the vehicle's network

Common causes

  • Faulty wiring or connectors in the communication network
  • Malfunctioning control modules
  • Corrupted software or firmware in control modules
  • Poor ground connections
  • Interference from aftermarket devices
  • Damaged or shorted communication lines
  • Low battery voltage or power supply issues
  • Faulty or damaged sensors

Common misdiagnoses

  • Faulty ABS module
  • Defective engine control module (ECM)
  • Malfunctioning body control module (BCM)
  • Wiring issues or shorts in the communication lines
  • Bad ground connections
  • Faulty sensors or actuators
  • Incorrectly programmed modules
  • Battery or charging system problems

Troubleshooting steps

  1. 1. Check for Additional 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

    Visually inspect the wiring and connectors related to the communication network. Look for signs of damage, corrosion, or loose connections

  3. 3. Pay special attention to the CAN (Controller Area Network) bus wiring, as this is often involved in communication issues

  4. 4. Check for Short Circuits or Open Circuits

    Use a multimeter to check for continuity in the communication lines. Look for any short circuits or open circuits that could disrupt communication

  5. 5. Test Modules

    Identify the modules that are part of the communication network (e.g., Engine Control Module, Transmission Control Module, Body Control Module)

  6. 6. Check if the affected modules are functioning properly. You may need to perform a module reset or reprogramming if necessary

  7. 7. Inspect for Interference

    Look for any aftermarket devices or modifications that may interfere with the vehicle's communication network. This includes alarms, stereo systems, or other electronic devices

  8. 8. Check Battery and Ground Connections

    Ensure that the vehicle's battery is in good condition and that all ground connections are secure. Poor power supply or grounding can lead to communication issues

  9. 9. Perform a Network Test

    If available, use a scan tool that can perform a network test to check the communication between modules. This can help identify which module is not communicating properly

  10. 10. Update Software/Firmware

    Check if there are any software or firmware updates available for the vehicle's modules. Sometimes, updating the software can resolve 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. 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 and repair. By following these troubleshooting steps, you can systematically identify and resolve the underlying issues causing the U1664 code