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
U0030
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
U0032
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
U0033
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
U0035
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
U0036
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
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