U1755 – Module Communication Failure

The ODBII code U1755 indicates a “Module Communication Failure,” meaning there is a problem with communication between the vehicle’s control modules, which may affect their ability to exchange data properly.

The severity of ODBII code U1755 is moderate.

Common Causes For: U1754 U1754: “Module Communication Failure”

• Faulty wiring or connectors
• Failed or malfunctioning module
• Poor ground connections
• Corroded or damaged pins
• Communication network issues (e.g., CAN bus problems)
• Software or firmware issues
• Intermittent electrical connections
• Low battery voltage or power supply issues

Common misdiagnosis for U1755 U1755: “Module Communication Failure”

• Faulty wiring or connectors
• Defective control modules
• Software issues or updates needed
• Battery or power supply problems
• Grounding issues
• Intermittent communication faults
• Other communication protocol failures

Common Troubleshooting Steps

The OBD-II code U1755 indicates a “Module Communication Failure,” which typically means that there is a problem with communication between various control modules in the vehicle. 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 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 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.
• Verify that the fuses related to the communication network are intact.
• Test Communication Lines:
• Use a scan tool to check the communication lines (CAN bus, LIN bus, etc.) for continuity and proper voltage levels.
• If you have access to an oscilloscope, you can check the signal waveforms on the communication lines to ensure they are functioning correctly.
• Inspect Modules:
• If possible, check the affected modules for any signs of physical damage or water intrusion.
• If you suspect a specific module is faulty, you may consider swapping it with a known good module to see if the issue resolves.
• Reset the Modules:
• Sometimes, simply resetting the modules can clear communication errors. Disconnect the battery for a few minutes, then reconnect it and see if the code returns.
• Check for Software Updates:
• Verify if there are any software updates available for the vehicle’s control modules. Sometimes, manufacturers release updates to fix communication issues.
• Scan Tool Communication:
• Ensure that your scan tool is compatible with the vehicle and can communicate with all modules. Some vehicles may require specific tools for certain modules.
• Consult Wiring Diagrams:
• Refer to the vehicle’s service manual for wiring diagrams to understand the communication network and identify any potential issues.
• 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 should be able to identify and resolve the underlying cause of the U1755 code.