U1914 – Module Communication Failure

The ODBII code U1914 indicates a “Module Communication Failure,” meaning there is a problem with communication between the vehicle’s control modules, often due to a fault in the wiring, connectors, or the modules themselves.

The severity of ODBII code U1914 is moderate.

Common Causes For: U1913 CAN Communication Bus – Missing Message.

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

Common misdiagnosis for U1914 U1914: “Module Communication Failure”

• Faulty wiring or connectors
• Defective control module
• Battery or power supply issues
• Software or firmware glitches
• Incorrectly configured or programmed modules
• Intermittent communication issues
• Grounding problems
• Other communication protocol failures

Common Troubleshooting Steps

The OBD-II code U1914 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(s). Look for signs of damage, corrosion, or loose connections.
• Pay special attention to the wiring harnesses that connect the modules, as these can be prone to wear and tear.
• Check Power and Ground:
• Ensure that the affected module has a proper power supply and ground connection. Use a multimeter to check for voltage at the module’s power and ground pins.
• If there is no power or ground, trace the wiring back to the source to identify any breaks or shorts.
• Test the Module:
• If possible, test the affected module to ensure it is functioning correctly. This may involve bench testing or swapping with a known good module.
• Some modules may have self-diagnostic capabilities that can provide additional information.
• Inspect the CAN Bus:
• The communication between modules often occurs over a Controller Area Network (CAN) bus. Check the integrity of the CAN bus wiring and connections.
• Use an oscilloscope or a CAN bus scanner to monitor the bus for proper communication signals.
• Check for Interference:
• Look for any aftermarket devices or modifications that may interfere with the vehicle’s communication network. This includes alarms, stereo systems, or other electronic devices.
• Reset the Codes:
• After performing any repairs or adjustments, clear the trouble codes using the OBD-II scanner and take the vehicle for a test drive to see if the code returns.
• Consult Technical Service Bulletins (TSBs):
• Check for any manufacturer-specific TSBs related to the U1914 code. There may be known issues or recalls that could provide guidance on resolving the problem.
• Professional Diagnosis:
• If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership. They may have specialized diagnostic tools and experience with the specific vehicle make and model. By following these steps, you can systematically diagnose and potentially resolve the U1914 code related to module communication failure.