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DTC codes / U06xx · Network communication / U065B

U065BLost Communication With Left Front Mode Actuator

U065B is a generic network communication code indicating that a control module on the vehicle's data bus has lost contact with the left front mode actuator, which is typically a motorized blend door actuator in the climate control system. The module that monitors this actuator (often the HVAC control module or body control module) sets the code when it stops receiving expected messages or feedback from the actuator over the communication network.

SystemNetwork
Code typeGeneric (all makes)
SeverityLow
Fix difficultyIntermediate
AreaNetwork communication

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

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