Komatsu Hydraulic Excavator Classification and troubleshooting steps
Procedure for troubleshooting
If a phenomenon looking like a trouble occurs in the machine, select a proper troubleshooting No. according
to the following procedure, and then go to the corresponding troubleshooting section.
1. Procedure for troubleshooting to be taken when user code and failure code are displayed on
If a user code and a failure code are displayed on the machine monitor, carry out the troubleshooting for
the corresponding “Display of code” according to the displayed failure code.
2. When electrical system failure code or mechanical system failure code is recorded in abnormality
If a user code and a failure code are not displayed on the machine monitor, check a mechanical system
failure code and an electrical system failure code with the abnormality record function of the machine
If a code is recorded, carry out troubleshooting for the corresponding “Display of code” according to the
a If an electrical system failure code is recorded, delete all the codes and reproduce them, and then see
if the trouble is still detected.
a A failure code of the mechanical system cannot be deleted.
a If a trouble is displayed in the air conditioner abnormality record or heater abnormality record by the
abnormality record function, carry out the corresponding troubleshooting in E-mode.
3. When user code and failure code is not displayed and no failure code is recorded in abnormality
If a user code and failure code are not displayed on the machine monitor and no failure code is recorded
in the abnormality record, a trouble that the machine cannot find out by itself may have occurred in the
electrical system or hydraulic and mechanical system.
In this case, check the phenomenon looking like a trouble again and select the same phenomenon from
the table of “Phenomena looking like troubles and troubleshooting Nos.”, and then carry out trouble-
shooting corresponding to that phenomenon in the “E-mode”, “H-mode”, or “S-mode.
Find more service info for Komatsu Hydraulic Excavator from
Komatsu Hydraulic Excavator Service Manual