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
U0038
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
U0040
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
U0041
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
U0043
Internal malfunction detected in ECM (CAN bus)
Mercedes Benz
Communication Network System
High severity
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