OBD fault code library
Look up any P or U code to see what it means, what causes it, the parts involved and how it gets fixed.
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Fault codes
U0023
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
U0024
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
U0026
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
U0027
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
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