U1561 – Module Communication Failure

The ODBII code U1561 indicates a “Module Communication Failure,” meaning there is a problem with communication between the vehicle’s control modules.

The severity of ODBII code U1561 is generally considered moderate.

Common Causes For: U1560 Communication Bus Fault.

• Faulty wiring or connectors
• Failed or malfunctioning control module
• Corrupted software or firmware in the module
• Poor ground connections
• Interference from aftermarket devices
• Low battery voltage or weak battery
• Communication network issues (e.g., CAN bus problems)
• Damaged or corroded pins in connectors
• Faulty or damaged sensors related to the module
• Incompatible or improperly installed modules

Common misdiagnosis for U1561 U1561: “Module Communication Failure”

• Faulty wiring or connectors
• Defective control modules
• Battery or charging system issues
• Software glitches or updates needed
• Grounding problems
• Intermittent communication issues
• Other communication protocol failures

Common Troubleshooting Steps

The OBD-II code U1561 indicates a “Module Communication Failure,” which typically means that there is a problem with communication between the vehicle’s control modules. Here are some common troubleshooting steps to diagnose and resolve this issue:

• Check for Other Codes: Use an OBD-II scanner to check for any additional trouble codes. Sometimes, U1561 may be accompanied by other codes that can provide more context about the issue.
• Inspect Wiring and Connectors:
• Visually inspect the wiring and connectors associated with the affected modules. 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 Power Supply: Ensure that the affected modules are receiving the proper voltage. Use a multimeter to check the power supply to the modules.
• Test Communication Lines:
• Use a scan tool to check the communication between modules. If possible, perform a network test to see if the modules can communicate with each other.
• Look for any short circuits or open circuits in the communication lines (CAN bus, LIN bus, etc.).
• Inspect Modules:
• If a specific module is suspected to be the cause, consider testing or replacing it.
• If you have access to a known good module, you can swap it out to see if the problem persists.
• Check for Software Updates: Sometimes, communication issues can be resolved with a software update. Check with the manufacturer for any available updates for the vehicle’s control modules.
• 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 returns.
• Consult Technical Service Bulletins (TSBs): Check for any TSBs related to the U1561 code for your specific vehicle make and model. Manufacturers may have issued guidance on common issues and fixes.
• Professional Diagnosis: If the issue persists after performing the above steps, it may be necessary to consult a professional technician or dealership for further diagnosis. They may have specialized tools and knowledge to pinpoint the problem. By following these steps, you can systematically identify and address the underlying cause of the U1561 code.