U2064 – Control Module Communication Bus Off.

The ODBII code U2064 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.

The severity of ODBII code U2064 is moderate to severe.

Common Causes For: U2063 Control Module Communication Bus Off.

• Faulty control module
• Damaged wiring or connectors
• Poor ground connections
• Communication bus short circuit
• Open circuit in the communication bus
• Faulty or disconnected CAN bus transceiver
• Interference from aftermarket devices
• Software or firmware issues in control modules

Common misdiagnosis for U2064 Control Module Communication Bus Off.

• Faulty control module
• Wiring issues
• Poor ground connections
• Corrupted software/firmware
• Faulty sensors
• Battery or power supply problems
• Intermittent connection issues
• Other communication bus faults (e.g., CAN bus issues)

Common Troubleshooting Steps

The OBD-II code U2064 indicates a communication issue on the control module communication bus, specifically that a module is “off” or not responding. This can be caused by various issues, including wiring problems, module failures, or issues with the communication bus itself. Here are some common troubleshooting steps to diagnose and resolve the U2064 code:

• Check for Additional Codes: Use an OBD-II scanner to check for any other trouble codes that may be present. This can provide additional context for the issue.
• Inspect Wiring and Connectors: Visually inspect the wiring and connectors associated with the control modules on the communication bus. Look for signs of damage, corrosion, or loose connections.
• Pay special attention to the ground connections, as poor grounding can lead to communication issues.
• Check the Communication Bus: Use a multimeter or an oscilloscope to check the voltage levels and signal integrity on the communication bus (CAN bus, LIN bus, etc.).
• Ensure that the bus is not shorted to ground or power, and that the termination resistors (if applicable) are present and functioning.
• Test Individual Modules: If possible, isolate and test each control module on the communication bus. This can help identify if a specific module is causing the issue.
• Disconnect each module one at a time and check if the code persists after each disconnection.
• Check for Software Updates: Verify if there are any software updates available for the control modules. Sometimes, communication issues can be resolved with a software update.
• Inspect for Physical Damage: Check for any signs of physical damage to the control modules themselves. Water intrusion, impact damage, or overheating can cause modules to fail.
• Perform a Hard Reset: Disconnect the vehicle’s battery for a few minutes to reset the control modules. Reconnect the battery and see if the code reappears.
• Scan for Communication Issues: Use a professional-grade scan tool to perform a network scan. This can help identify which module is not communicating properly.
• Check Power Supply to Modules: Ensure that all control modules are receiving the proper voltage and ground. Use a multimeter to check the power supply to each module.
• Consult Service Manual: Refer to the vehicle’s service manual for specific diagnostic procedures related to the U2064 code and the communication bus used in your vehicle.1
• 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 should be able to identify and resolve the underlying issue causing the U2064 code.