U2614 – Control Module Communication Bus Fault

The ODBII code U2614: Control Module Communication Bus Fault indicates a problem with the communication between control modules in the vehicle, suggesting that one or more modules are not able to communicate properly over the vehicle’s data bus.

The severity of ODBII code **U2614: Control Module Communication Bus Fault** is generally considered moderate to severe.

Common Causes For: U2606: CAN Bus Communication Fault

• Faulty control module
• Damaged wiring or connectors
• Poor ground connections
• Short circuits in the communication bus
• Open circuits in the communication bus
• Interference from aftermarket devices
• Corroded connectors
• Software issues or bugs in the control module
• Low battery voltage or power supply issues
• Faulty communication bus transceiver

Common misdiagnosis for U2614: Control Module Communication Bus Fault

• Faulty control module
• Wiring issues or shorts
• Poor ground connections
• Corroded connectors
• Battery or power supply problems
• Software or firmware issues
• Other communication bus faults (e.g., CAN bus issues)
• Intermittent electrical connections
• Faulty sensors or actuators
• Incorrectly installed aftermarket accessories

Common Troubleshooting Steps

The OBD-II code **U2614: Control Module Communication Bus Fault** indicates a communication issue between control modules in a vehicle’s network. This can be caused by various factors, including wiring issues, faulty modules, or problems with the communication protocols. 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. This can provide more context about the issue.
• Inspect Wiring and Connectors:
• Visually inspect the wiring harnesses and connectors associated with the control modules. Look for signs of damage, corrosion, or loose connections.
• Pay special attention to the communication lines (CAN bus, LIN bus, etc.) for any signs of wear or damage.
• Test the Control Modules:
• If possible, test the affected control modules to ensure they are functioning correctly. This may involve using a scan tool to communicate with each module individually.
• If a specific module is unresponsive, it may need to be replaced.
• 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 be causing the communication failure.
• 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.
• Verify Power Supply:
• Check that the control modules are receiving the correct voltage. A low or unstable power supply can affect module performance.
• Look for Interference:
• Check for any aftermarket devices or modifications that may interfere with the vehicle’s communication network. This includes alarms, stereo systems, or other electronic devices.
• Perform a Network Scan:
• Use a professional-grade scan tool to perform a network scan. This can help identify which modules are communicating and which are not.
• Reset the Modules:
• Sometimes, resetting the control modules by disconnecting the battery for a few minutes can clear temporary communication faults.
• 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 issues related to communication faults. 1
• Seek Professional Help:
• If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician who specializes in automotive electronics. By following these troubleshooting steps, you can systematically identify and resolve the underlying cause of the U2614 code.