U1915 – Module Communication Failure

The ODBII code U1915 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 U1915 is moderate.

Common Causes For: U1914 U1914: “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
• Low battery voltage or power supply issues
• Intermittent electrical connections

Common misdiagnosis for U1915 U1915: “Module Communication Failure”

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

Common Troubleshooting Steps

The OBD-II code U1915 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 is receiving proper power and ground. Use a multimeter to check 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 Affected Module:
• If the module is accessible, you can perform a bench test or swap it with a known good module to see if the problem persists.
• If the module is integrated into a larger system (like a body control module), you may need specialized equipment to test it.
• Check for Communication:
• Use a scan tool to check if the affected module is communicating with other modules. If it is not, there may be a fault in the module itself or in the communication lines.
• You can also use a scope to check the data lines for proper signals.
• Inspect the CAN Bus:
• If your vehicle uses a Controller Area Network (CAN) bus, check for issues with the bus itself. Look for short circuits, open circuits, or interference.
• You can use a CAN bus analyzer to monitor the communication on the bus.
• Update Software/Firmware:
• Check if there are any software or firmware updates available for the affected module. Sometimes, communication issues can be resolved with an update.
• 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 Service Manual:
• Refer to the vehicle’s service manual for specific diagnostic procedures related to the U1915 code and the affected module.
• Seek Professional Help:
• If you are unable to resolve the issue after these steps, it may be best to consult a professional mechanic or technician who has experience with your specific vehicle make and model. By following these steps, you should be able to identify and resolve the underlying issue causing the U1915 code.