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Komatsu PC78

TANDWTRUCKING ยท 2021-03-15 08:03

Can somebody point me in the right direction. The machine is new to me. Just starting to become familiar with the machine. Was digging out some stumps the other day and while digging the engine goes into what I can eco mode where the engine returns to idle even though I'm digging with it. There doesn't appear to be a switch to turn this option off. The excavator doesn't seem to do it when I'm traversing over the ground, just when I'm digging....

Replies11
  1. #1mutti_wilson2021-03-15 14:07

    While digging or are you not moving the sticks for a few seconds?

  2. #2TANDWTRUCKING2021-03-15 23:04

    No, it happens while I'm moving the sticks.

  3. #3John C.2021-03-16 00:40

    Can you give us the total model number and serial number? Cab you post a photo of the monitor panel so we know what you have?

  4. #4TANDWTRUCKING2021-03-17 00:14

    John C, here is the serial I.D tag and the monitor panel.

  5. #5John C.2021-03-17 00:27

    You have a different monitor panel than what I normally see. Since it does have a display, I'm going to assume that there is a diagnostic mode. Can you check the back of the monitor for a button that is inside a hole in the upper right hand corner? I have a video that shows how to get into a monitor that was meant for a machine built for this country.

  6. #6TANDWTRUCKING2021-03-17 00:37

    Will check it out 2maro.

  7. #7LACHAU2021-03-17 01:58

    It is a US dash 6 series for the Norwegian and North American markets. Its gauge cluster is different from the conventional dash 6 series, buddy.

  8. #8steve waldner2021-03-18 08:23

    I got a machine exactly like this , what do u wanna know? I know it has a motorized throttle , and when u hit the joystick button it throttles down , check for stuck button , also when u travel does it rev up right away? The joy button is idle button , not sure if eco has to be pressed on display or not .

  9. #9John C.2021-03-18 10:35

    I've been informed that instead of a button behind the monitor panel, the alarm cancel button down by the engine throttle dial is used. If you push the alarm cancel button and the top left button which is the mode selector at the same time, it will shift the display to the diagnostic mode. In your photo I see the outlines of two buttons that are not marked. Those would normally have arrows on them. You should be able to press those to shift modes from fault code and monitor modes. 01 on the display means you are at the fault code mode. 02 means you are at the monitor mode. Once you get where you want to be, there is another button to the right of the travel speed button. Hold the alarm cancel button and press that hidden button at the same time and you should be able to see the codes. The key is to hold the alarm cancel button when you wish to make changes.

  10. #10TANDWTRUCKING2021-03-18 23:48

    Steve, Yes I think I figured out the problem. I recently had removed my joysticks to trace my pilot lines. I converted the machine over to J/D operation and in doing so the left joystick must not have gotten tightened up all the way. I tightened the joystick up and have loaded about 100 ton of sand and haven't had an issue since. Seems that was the issue. Thanks for offering some advice.

  11. #11TANDWTRUCKING2021-03-18 23:52

    John C. I think i figured out the issue, read above post. I will refer back to your information above for future issues. Thanks again.