U1553 – Class 2 Data Bus Communication Failure

The ODBII code U1553: Class 2 Data Bus Communication Failure indicates a malfunction in the Class 2 data bus communication system, which affects the transmission of data between various electronic control units (ECUs) in the vehicle.

The severity of ODBII code U1553: Class 2 Data Bus Communication Failure is generally considered moderate to severe, as it can affect communication between modules in the vehicle.

Common Causes For: U1552 Lost Communication with Instrument Panel Cluster (IPC)”.

• Faulty wiring or connectors in the Class 2 data bus.
• Malfunctioning control modules.
• Poor ground connections.
• Interference from aftermarket devices.
• Corroded or damaged terminals.
• Software issues or bugs in the control modules.
• Low battery voltage or power supply issues.
• Faulty or damaged data bus transceiver.

Common misdiagnosis for U1553 U1553: Class 2 Data Bus Communication Failure

• Faulty wiring or connectors
• Defective control modules
• Battery or power supply issues
• Grounding problems
• Intermittent communication issues
• Software or firmware glitches
• Incorrectly installed aftermarket accessories
• Faulty sensors or actuators

Common Troubleshooting Steps

The OBD-II code U1553 indicates a Class 2 Data Bus Communication Failure, which typically relates to issues in the communication between various modules in a vehicle’s network. 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 Class 2 data bus. Look for signs of damage, corrosion, or loose connections.
• Pay special attention to the connectors at the modules involved in the communication.
• Check for Short Circuits:
• Use a multimeter to check for short circuits in the wiring harness. A short can disrupt communication between modules.
• Test Modules:
• If you suspect a specific module is causing the issue, you can test it by disconnecting it and checking if the code persists.
• If the code clears after disconnecting a module, that module may be faulty.
• Inspect Ground Connections:
• Ensure that all ground connections related to the data bus are secure and free of corrosion. Poor ground connections can lead to communication failures.
• Check for Interference:
• Look for any aftermarket devices or modifications that may interfere with the data bus communication. This includes alarms, stereo systems, or other electronic devices.
• Scan for Module Communication:
• Use a scan tool to check if all modules on the Class 2 data bus are communicating properly. Some scan tools can perform a network test to identify communication issues.
• Update Software/Firmware:
• In some cases, updating the software or firmware of the vehicle’s modules may resolve communication issues. Check with the manufacturer for any available updates.
• Perform a Battery Reset:
• Disconnect the vehicle’s battery for a few minutes to reset the modules. Reconnect and see if the code reappears.
• Consult Service Manual:
• Refer to the vehicle’s service manual for specific diagnostic procedures related to the Class 2 data bus and any specific tests recommended by the manufacturer. 1
• Professional Diagnosis:
• If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or dealership for further diagnosis. They may have specialized tools and knowledge to pinpoint the issue. By following these steps, you can systematically identify and address the cause of the U1553 code.