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Kobelco SK150 MIII CPU code electrical problems

Discussion in 'Excavators' started by cat765, Dec 30, 2008.

  1. cat765

    cat765 Member

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    I am new to Heavy Equip. Forums and glad to have found it. Lots of good info.

    This past fall my Kobelco SK 150 started to throw up a code CPU on the display. Basically the motor would idle way down, past low idle, then snap out of it and run fine for a while. Sometimes I would have no throttle control, sometimes the auto accel green L.E.D. indicator light would flash. Sometimes the CPU code would come up on the dispaly and stay on and sometimes would flash really fast on the sreen.

    I contacted 2 Kobelco dealers about the problem, one wanted to sell me a new computer and the other said it was probably a short in a wire some place and the computer was probably OK.

    Has any one ever had a problem similiar to this? I'm interested and open for any suggestions it may be before I haul it to the Kobelco dealer.

    Thanks,

    Carter
     
  2. cps

    cps Senior Member

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    Hi cat765, I had a kobelco sk60 that throw up cpu when tracking over rough ground it was the main concecting plug behind the seat was loose, theres a screw rite threw the middle to tightn it up! Also you could check if thers a trottle cable to a stepping motor may be sezing up! had a problem like this also on a hitachi ex model< not sure what system kobelco use! Any way i would check all the conections around the cab I.E behind the seat! Hope this helps, let me know how you get on? cps
     
  3. cat765

    cat765 Member

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    Thanks cps, i did check all the connections everywhere and I assume you are talking about the main plug going into the computer. I also checked the main plugins into the computer. As far as the stepping motor goes, the linkage looks good and it seems to be fine.

    Has anyone had a problem with a speed sensor? Just another thought I had that may be causing the problem.

    thanks for suggestions,

    Carter
     
  4. Johnny English

    Johnny English Well-Known Member

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    Hi there, I feel your pain we have a FH EX135W 2002 that is of the same pedigree with diferent colours and badges, our machine has always got electrical faults of many kinds, pity really cause its a cracker when its running. Our main dealer doesn't know here to start looking, fuses scattered all over on it. Nobody but main dealer will entertain it either, and their not keen.
     
  5. cps

    cps Senior Member

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    Speed sensor

    good call cant say i have had any problems with this on a kobelco, i guess you also checked the main plug were the harness comes into the cab, thats the one that give me bother! Whats the Kobelco service like in your area, around here and in Ireland and the Uk in general its not that good! No one stocks parts or has any info (wiring diagrams etc) its a case of every man for himself!
     
  6. Johnny English

    Johnny English Well-Known Member

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    Contracts manager, Civil Engineering contractor
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    HM plant come out to our machine well enough, but don't know what to do when their there. All our parts come with New holland on them though. We have to rely on the fitter having a few mates in the trade that might know where to look. Plus they don't have software to plug into our machine. We got caught up in the period where they both made it but neither want to maintain it. I dread it breaking down. Shame cause its a beast when it runs.
     
  7. cat765

    cat765 Member

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    There is one Kobelco dealer in Minnesota and I think they are a good dealer. Does anyone deal with Carlson Tractor for Kobelco service and repairs?
     
  8. qkoop

    qkoop Active Member

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    I had a check wrench on my display,turned out to be the gauge controller.It sounds like the computer under the seat or a bad connection.I have the complete harness testing kit for the mark III machines if your stuck.
     
  9. cat765

    cat765 Member

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    Hi gkoop, what does the harness testing kit do exactly? Is it for doing the A adjustment? The service manager at the dealer told me a little bit about it, so I was just curious.
     
  10. dirthog

    dirthog Senior Member

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    electric problems

    very carefully check the wire harness where it comes out of the computer and bends down into the machine the older machines at times would rub the insulation off the wires there and cause a short you would have to remove all the plugs from the computer and fold the wires up to check them it would be a very small spot on the wire
     
  11. cat765

    cat765 Member

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    I will check that spot out. I hope I find a wire that is snorting out rather than a $2500 computer plus the labor. Thanks dirthog
     
  12. qkoop

    qkoop Active Member

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    The manual says electrical and mechatronics.IT doesnt show the 150 mIII .Just the 100,120,140c,200,200c,220,240c.What yyear is your machine?
     
  13. cat765

    cat765 Member

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    gkoop, it's a '94.
     
  14. qkoop

    qkoop Active Member

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    It should work then.It comes with all the harnesses to hook between all the different connections and with the manual it tells you what the values should read.If the values are out it tells you what the problem is and what to change.Does ecu flash up steady or does it come and go?if it comes and goes i would say bad connection.I would try taking out the seat and unplugging and wiggling the harnness that goes into the kpss controller.Make sure the key is off when you do it.
     
  15. cregadkins

    cregadkins Member

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    I used to work for a Kobelco dealer. If I remember correctly, the CPU warning is generally caused by either a bad fuse or a failed CPU. Of course, wiring could cause it also. The symptoms you described make me wonder about a couple other things too. If this only happens when the throttle is at wide open, you could check this by throttling down just a little and running it, could be that adjusting the "Stepping Motor" which is the electrical motor that runs the throttle, will help. This is what your dealer referred to as the "A" adjustment. If the throttle lever makes contact with the stop screw it can cause this to happen. There should be a small gap between the throttle lever and the stop screw when it is at wide open. If there is not a small gap there, you would need to have the "A" adjustment performed. It may be difficult to determine why this is happening due to the intermittant nature of the problem. One other thing to check would be the two wiring connectors that hook the stepping motor to the machine harness. Good luck!
     
  16. MR. KOBELCO

    MR. KOBELCO Resigned

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    Cpu code

    In most cases the result of what you are describing is that the fuse for the computer ( c-1 controller ) is not being held tightly (making good contact) in the fuse panel itself.
    When the machine acts up just simply wiggle the fuse and see if the code goes away after about 5-10 seconds.
    The 5-10 seconds is the time it takes for the computer to scan thru the inputs and outputs of the computer.
    You can remove the fuses and pinch the contacts attempting to make them hold the fuse tighter.
    I find this works only for awhile but eventually you will need to buy a new fuse panel assy.. It does not cost too much.
    The controller fuses are the 5 amp fuses.
    There are generally two.
    1 controller and 1 backup.
     
  17. cat765

    cat765 Member

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    Mr. Kobelco, I took my machine to the Kobelco dealer and after they did some trouble shooting and looking for bad grounds and wires etc., they said it is the computer... which sucks but if that fixes the problem, I will be glad. How ever, when I get it back and the CPU code comes back, then I will be upset, and will see if it is what you mentioned.
     
    Last edited: Apr 9, 2009