A DTC 55 is used to end all DTC messages. This code does not show on the DRB tool and indicates a completion of the stored codes on the Malfunction Indicator Lamp (check engine lamp).
ECM PCM - Circuit error or EGR valve solenoid 3 - Circuit error ( Depending on the car model )
Converter error or pcm not grounded or lean fuel or founded reference voltage
Idle air control valve
End of message.