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U code network High severity

U2073 Control Module Communication Bus Off

The OBD2 code U2073 indicates a communication issue where a control module is not able to communicate on the vehicle's communication bus, often due to a fault in the module or wiring

Definition

The OBD2 code U2073 indicates a communication issue where a control module is not able to communicate on the vehicle's communication bus, often due to a fault in the module or wiring

Common causes

  • Faulty control module
  • Damaged wiring or connectors
  • Poor ground connections
  • Communication bus short circuit
  • Open circuit in the communication bus
  • Corroded connectors
  • Software issues or firmware corruption
  • Intermittent electrical issues
  • Faulty or incompatible aftermarket components

Common misdiagnoses

  • Faulty control module
  • Wiring issues
  • Poor ground connections
  • Corrupted software/firmware
  • Faulty connectors
  • Battery or power supply issues
  • Other communication bus errors
  • Sensor malfunctions

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other related trouble codes. This can provide more context about the issue and help identify which module is having communication problems

  2. 2. Inspect Wiring and Connectors

    Visually inspect the wiring and connectors associated with the control modules. Look for signs of damage, corrosion, or loose connections. Pay special attention to the CAN bus wiring

  3. 3. Check Power and Ground

    Ensure that the affected control module has proper power and ground. Use a multimeter to check voltage at the module's power supply and ground connections

  4. 4. Test the Control Module

    If possible, test the control module that is reporting the U2073 code. This may involve bench testing or swapping with a known good module to see if the problem persists

  5. 5. Inspect the CAN Bus

    Use an oscilloscope or a CAN bus analyzer to check the integrity of the CAN bus signals. Look for any abnormal signals, noise, or interruptions in communication

  6. 6. Check for Short Circuits

    Inspect the wiring for any short circuits or open circuits that could be affecting communication. This includes checking for shorts to ground or power

  7. 7. Look for Intermittent Issues

    Sometimes, communication issues can be intermittent. Pay attention to when the code appears (e.g., during specific driving conditions) and check for any patterns

  8. 8. Update or Reprogram Modules

    If the control module is functioning but still reporting the code, check if there are any software updates or reprogramming procedures available from the manufacturer

  9. 9. Clear Codes and Test Drive

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

  10. 10. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to the U2073 code for your specific vehicle make and model. Manufacturers may have specific recommendations or known issues.1

  11. 11. Seek Professional Help

    If the issue persists after performing the above steps, it may be necessary to consult a professional mechanic or technician who has experience with automotive electronics and communication systems. By following these troubleshooting steps, you can systematically identify and resolve the underlying issue causing the U2073 code