Hello all- I have a 2007 Komatsu PC78US. Batteries went dead- removed, charged, reinstalled. Machine started but ran poorly with black smoke. Found intake clogged with mouse nest. Cleaned that all out, started and idled perfectly and clean. Issue I am having now is that there is no rpm increase when commanded. The turtle is also on the display- but I don’t remember if this disables the throttle or not. I’m in the process of disconnecting the “turtle” mode button as it was always a little touchy, maybe it’s stuck on? If this doesn’t work does anyone have another direction to look? Thanks!
Hello. Is it PC78US-6? Is there any user error code (for example E05)? Might be related to governor control system (fuel dial, governor motor, engine speed sensor, controller and their harness). If you see E05 user error code, I can help how to go further to be able to see detailed service code if it's dash 6 machine. Turtle button stands for travel speed only in Komatsu excavators.
Can you take a photo o the monitor panel and post it here? In many cases the mini and midi excavators are set up differently than the larger machines.
Hi! I’ve got the same errors and got the code E05 on the display. My machine is a Komatsu PC78US-6. Can you help me how to diagnose it more precisely? Best regards, Lars from Norway
I don't see where the original poster ever came back. The EO5 is an operator code which means governor control system. What you need to do next is to put the monitor panel in SERVICE MODE and then read off the codes and post them on here. For some reason I can't get the graphic to show that tells you what each button on the monitor panel does. See if you can figure out the description below. Let me know if you need more help. TROUBLESHOOTING DISPLAY AND SPECIAL FUNCTIONS OF MONITOR PANEL PC78US-6 20-247 b 3. Function of displaying "service code" All trouble information items of the controller are sent to the monitor panel. All of the information items which must display "user codes" and those which do not need display "user codes" are saved as "service codes" in the monitor panel. If the following operation is executed, the service code is displayed on the display of the monitor panel and the letter "E" to indicate that the trouble is happening currently and the lapse time (service meter reading) are displayed on the service meter unit. 1) Method of displaying and deleting service code (1) Display (5) Set switch i) The service code is displayed by the following procedure: (2) Service meter unit (6) Travel speed switch B Push and hold the "Buzzer cancel switch (8)" and "Working mode selector switch (7)" for 2.5 seconds. (3) Mode selector switch (UP) (7) Working mode selector switch C Push the "Buzzer cancel switch (8)" and "Mode selector switch (UP) (3)" [or Mode selector switch (DOWN) (4)] and set "01" to the 2nd and 3rd columns from the left on service meter unit (2). (4) Mode selector switch (DOWN) (8) Buzzer cancel switch D Push the "Set switch (5)". Since the switches "3, 4, and 5" are not indicated on the panel of model US, operate the same parts as the panel of model UU. Example 1)"01" is displayed on service meter unit (2).