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DTC codes / U04xx · Invalid data received from a module / U04AF

U04AFInvalid Data Received From Hybrid/EV Battery Interface Control Module O

U04AF is a communication fault indicating that a control module received invalid or corrupted data from the hybrid/EV battery interface control module O. The computer detected that the data stream from this module did not match expected values or was missing critical information, so it flagged the message as invalid rather than trusting it.

SystemNetwork
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyProfessional
AreaInvalid data received from a module

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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