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Komatsu PC128 UU-1

wbvs58 ยท 2014-02-20 19:43

I am hoping that someone might be able to help me with a problem with my machine. My neighbour has been using it and he had an alarm go off while moving forward with the arm extended. The light that has come on and flashes with the beeping is on the lower left of the small console. It doesn't seem to be associated with the engine but the writing on it is Japanese. The arm will not extend or lift now. Similar problems have occurred in the past and I have fixed it by turning it off then turning the key to the left and then starting it but this time this reset procedure has not fixed it. I have disconnected the arm on the sensor at the point the boom extends and moved that in but to no avail it still beeps at me. Does anyone have any suggestions to help me out or suggest ways to bypass this to get the arm in and lifted so that we can get it to a better position to work on it. Any help would be greatly appreciated. Ken

Replies5
  1. #1wrc2014-02-20 20:06

    On the control panel there should be a switch turn it left to clear and hold it there for about two seconds. It should say clear on the left and set on the right if it gets bumped to set it will stop you boom up/down in the set location s well as your stick in/out. Hope this helps Eric.

  2. #2wbvs582014-02-21 06:48

    Thanks for that Eric. I did try like you suggested but no success unfortunately. Ken

  3. #3heymccall2014-02-21 20:45

    On my 128UU-2, the cab protection system can be overridden by holding up the momentary toggle under the right front corner of the seat. As long as you hold it up, you should have full control of the implement cylinders, including the ability to hit the cab with the bucket.

  4. #4wbvs582014-02-22 03:34

    Thanks heymcall. I found that switch but it seems to have 3 positions, I forget where it is but I think it is up, the middle position seems to make all the electrics dead and the bottom position a loud horn sounds but I must admit in this position I didn't try moving anything, none of those positions are spring loaded. I'll have to have another look at it tomorrow. Ken

  5. #5wbvs582014-02-23 00:54

    Just an update on my problem. We are rolling again. I had a good look in the manual I had downloaded and from that I realised that an error code 34 that appeared on the control panel was not that the bucket was 34 metres down but was an error code suggesting that there was a fault in the potentiometer or wiring of the offset of the boom sensor (it has one of those knuckle booms). We had been up there before looking at the wires etc and all looked OK but with this added knowledge a better look revealed a broken wire going into a connector and once this was fixed we were back in business. It has been a good exercise as I have a lot more knowledge of the machine now, things that were a bit of a mystery I am more familiar with now. Thanks for your help. Ken