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

U0012 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0015 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0016 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0019 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0022 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0025 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0028 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0029 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0031 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0034 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0037 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0039 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0042 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0045 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity
U0048 Internal malfunction detected in ECM (CAN bus)
Mercedes Benz Communication Network System High severity

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