U2680 – Control Module Communication Bus Fault

The ODBII code U2680: Control Module Communication Bus Fault indicates a communication issue between control modules in the vehicle, suggesting that one or more modules are not properly communicating over the vehicle’s data bus.

The severity of ODBII code U2680 is moderate.

Common Causes For: U2679 Lost Communication with the Steering Angle Sensor.

• Faulty control module
• Damaged wiring or connectors
• Poor ground connections
• Corroded terminals
• Short circuits in the communication bus
• Intermittent electrical connections
• Software issues or bugs in the control module
• Faulty or incompatible aftermarket parts
• Low battery voltage or power supply issues
• Environmental factors (moisture, heat, etc.) affecting connections

Common misdiagnosis for U2680 U2680: Control Module Communication Bus Fault

• Faulty control module
• Wiring issues
• Poor ground connections
• Corrupted software/firmware
• Faulty sensors
• Battery or power supply problems
• Intermittent connection issues
• Communication protocol errors

Common Troubleshooting Steps

The OBD-II code U2680 indicates a “Control Module Communication Bus Fault.” This code typically points to a problem with the communication between various control modules in the vehicle. Here are some common troubleshooting steps to diagnose and resolve this issue:

• 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.
• 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 communication bus wires (CAN bus) for any signs of wear or damage.
• 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.
• Test Control Modules: If possible, test the control modules involved in the communication bus. This may involve checking for proper operation or replacing a suspected faulty module.
• Inspect Ground Connections: Ensure that all ground connections for the control modules are secure and free of corrosion. Poor grounding can lead to communication issues.
• Check for Interference: Look for any aftermarket devices or modifications that may interfere with the communication bus. This includes alarms, stereo systems, or other electronic devices.
• 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.
• Update Software/Firmware: Check if there are any software or firmware updates available for the control modules. Sometimes, updating the software can resolve communication issues.
• Clear Codes and Test Drive: After performing any repairs or adjustments, clear the trouble codes and take the vehicle for a test drive to see if the code reappears.
• Consult Service Manual: Refer to the vehicle’s service manual for specific diagnostic procedures related to the communication bus and control modules.1
• Seek Professional Help: If the issue persists after performing the above steps, consider seeking help from a qualified mechanic or automotive technician who has experience with your vehicle’s make and model. By following these steps, you should be able to identify and resolve the underlying issue causing the U2680 code.