U2187 – Module Communication Failure

The ODBII code U2187 indicates a communication failure between modules in the vehicle’s network, suggesting that one or more electronic control units (ECUs) are not communicating properly with each other.

The severity of ODBII code U2187 is moderate.

Common Causes For: U2186 U2186: Control Module Communication Bus Fault

• Faulty wiring or connectors
• Failed control module
• Poor ground connections
• Corroded or damaged pins
• Intermittent communication issues
• Software or firmware issues
• Low battery voltage
• Electrical interference
• Faulty CAN bus system
• Incompatible or missing modules

Common misdiagnosis for U2187 U2187: “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 in the network

Common Troubleshooting Steps

The OBD-II code U2187 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.
• If the module is not receiving power, trace the wiring back to the fuse box and check for blown fuses or damaged wires.
• Test the Module:
• If possible, test the affected module by swapping it with a known good module (if applicable) to see if the problem persists.
• Some modules may have self-diagnostic capabilities that can provide additional information.
• Inspect the CAN Bus:
• The Controller Area Network (CAN) bus is responsible for communication between modules. Check for any issues with the CAN bus wiring, such as shorts or opens.
• Use an oscilloscope or a CAN bus diagnostic tool to monitor the bus for proper communication signals.
• Check for Software Updates:
• Sometimes, communication issues can be resolved with a software update. Check with the vehicle manufacturer for any available updates for the affected module.
• Clear Codes and Test Drive:
• After performing any repairs or inspections, clear the trouble codes using the OBD-II scanner 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 U2187 code and the affected module.
• Professional Diagnosis:
• If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership with experience in diagnosing module communication issues. By following these steps, you should be able to identify and resolve the underlying cause of the U2187 code.