What are the common causes of U067D?

A fan 4 control module that stopped answering on the CAN bus. A broken or chafed wire in the fan 4 communication circuit. Corrosion or water in the fan 4 connector. Loss of power or ground at the fan 4 module. An internal fault in the fan control module.

Check for power and ground at the fan 4 module. Inspect the fan 4 connector for corrosion or water. Test the CAN wires to the fan 4 module for opens and shorts. Command the fan with a scan tool and watch for a response. Replace the fan 4 control module if it stays silent. Clear the code and retest.

U067D

Lost Communication With Fan 4

System: Network communication (U code)
Lamp: Check Engine Light
Category: Network Communications

What it means

U067D means Lost Communication With Fan 4.

Check these first

A fan 4 control module that stopped answering on the CAN bus
A broken or chafed wire in the fan 4 communication circuit
Corrosion or water in the fan 4 connector
Loss of power or ground at the fan 4 module
An internal fault in the fan control module

What to do next

Check for power and ground at the fan 4 module
Inspect the fan 4 connector for corrosion or water
Test the CAN wires to the fan 4 module for opens and shorts
Command the fan with a scan tool and watch for a response
Replace the fan 4 control module if it stays silent
Clear the code and retest

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Updated

Generic SAE J2012 definition. Last updated 2026-10-10.