U1928 – Module Communication Failure

The ODBII code U1928 indicates a “Module Communication Failure,” meaning that 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 U1928 is moderate.

Common Causes For: U1927 U1927: “Module Communication Failure”

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

Common misdiagnosis for U1928 U1928: “Module Communication Failure”

• Faulty wiring or connectors
• Defective control module
• Software issues or updates needed
• Power supply problems
• Grounding issues
• Intermittent communication issues
• Other module failures
• Corrupted data or configuration errors

Common Troubleshooting Steps

The OBD-II code U1928 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 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 module. 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 module is receiving the proper voltage. Use a multimeter to check the power supply to the module.
• Verify that the fuses related to the module are intact and functioning.
• Test the Module:
• If possible, test the affected module to ensure it is functioning correctly. This may involve using specialized diagnostic tools or swapping the module with a known good one.
• Check for Interference:
• Look for any aftermarket devices or modifications that may interfere with the communication network, such as alarms, remote starters, or other electronic accessories.
• Inspect the CAN Bus:
• If the vehicle uses a Controller Area Network (CAN) bus, check for issues with the bus itself. This may involve checking for short circuits, open circuits, or other faults in the wiring.
• Use a CAN bus diagnostic tool to monitor the communication on the bus.
• Reset the Modules:
• Sometimes, simply resetting the modules can resolve communication issues. This can be done by disconnecting the battery for a few minutes or using a scan tool to clear the codes.
• Update Software/Firmware:
• Check if there are any software or firmware updates available for the vehicle’s modules. Sometimes, communication issues can be resolved with an update.
• Consult Technical Service Bulletins (TSBs):
• Look for any TSBs related to the specific make and model of the vehicle. Manufacturers may have issued guidance on known communication issues.
• Professional Diagnosis:
• If the issue persists after performing the above steps, it may be necessary to seek professional assistance. A qualified technician can perform more advanced diagnostics and repairs. By following these steps, you can systematically identify and address the underlying cause of the U1928 code.