U1982 – Module Communication Failure

The ODBII code U1982 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 U1982 is moderate.

Common Causes For: U1981 Lost Communication with the Body Control Module (BCM).

• 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 U1982 U1982: “Module Communication Failure”

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

Common Troubleshooting Steps

The OBD-II code U1982 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 modules. 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 modules are receiving the proper voltage. Use a multimeter to check the power supply to the modules.
• Verify that the fuses related to the communication network are intact.
• Test Communication Lines:
• Use a scan tool to check the communication lines (CAN bus, LIN bus, etc.) for continuity and proper voltage levels.
• If you have access to an oscilloscope, you can check the signal waveforms on the communication lines to ensure they are functioning correctly.
• Inspect Modules:
• If possible, check the affected module for any signs of internal failure. This may involve removing the module and inspecting it for physical damage.
• If you have access to a known good module, you can swap it in to see if the problem persists.
• 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.
• Check for Software Updates:
• Check if there are any software updates available for the vehicle’s control modules. Sometimes, communication issues can be resolved with a software update.
• Look for Interference:
• Ensure that there are no aftermarket devices (like alarms, remote starters, etc.) that could be interfering with the communication network.
• Consult Wiring Diagrams:
• Refer to the vehicle’s service manual for wiring diagrams and communication protocols to better understand how the modules communicate and where potential issues may lie.
• Professional Diagnosis:
• If the issue persists after performing the above steps, it may be necessary to consult a professional technician who has experience with the specific vehicle make and model. They may have specialized tools and knowledge to diagnose complex communication issues. By following these steps, you should be able to identify and resolve the underlying cause of the U1982 code.