We have a kumatsu pc75 uu-2, was running fine. Now we went to use it and have no stick function at all. The saftey switch seems to work, energized when lever is up and not energized when down. Blade moves up and down and tracks turn. Any ideas?
If all the other controls work then it just in the circuit for the stick. This will also tell you if you have a pilot problem or a delivery problem. If none of them work then look at all you filters first(pilot and main hydraulic filter). Its cheap easy and you will know if there was a failure(depending on type of material in filter will be type of failure). At that point then you have narrowed down to what side of the hydraulic it is. Hopefully this gets you started and I hope to read the result when you find something.
Do you have a pattern selector? I have seen them get out of position and make a machine function funky. Is it just the boom or all of the boom functions?
good call caterpillarmech, very good possibility, that gives me an idea on another problem I'm working on.
Have no boom function at all, have continuity on both wires to solinoid for safty switch which makes me think electrical problem. No pattern select, and is a grey market machine.
I am having the same issue. I know it's an old thread but I am wondering how you made out?
No answers, am checking pilot pump this weekend. It seems electrical to me. I have power on both sides of the lock out solinoid, which seems odd. Let me know if you get anywhere. Good luck
Had komatsu send over all wiring for cab and controls. Looking at it now. Their diagrams are not what I'm used to
I'm having a similar problem, blade move and tracks move but no control lever function. If you use the safety by-pass switch all functions work. All hydraulics work, good pressure at test ports. Code on console is "EE" and code on the controller is blank. Its a PC75UU-2.
Where is the safety bypass located?
Below your right knee when in the seat on the side of the seat mount.
Does your machine have any codes on the console or the controller?
Safry bypass switch did not work, controller Shows 3.6.
Looks like you may have a bad offset potentiometer. We have had those go bad, over the years. We have not had a 'EE' code, it says that the controller is bad, but on a 1995 machine the price of the controller is $6,900.00 it is not worth buying. I'm hoping somebody may have something I missed?
What does the EE code mean? I have one and I don't have power to my sticks. But I have had the EE code since I owned it (10 years)
I have power to the one side of the lockout solenoid but no power to the other one. I do get the ground to activate when I put the safety lever down. Do you get the ground to activate on yours?
I found that power is going in but not coming out. But the test for 'EE' is "is there power at K1, #8, #17, #18, if so the controller is bad." That a very basic test to replace a $6,900.00 controller. How have you been using the machine? Did you bypass something like the safety switch?
I didn't bypass anything it always worked. Always had the EE on
Do you have a safety bypass switch? If so has it been bypassed, electrically or may be hydraulically? Ours won't work unless you hold the switch up. It is not labeled in english, the operators did not know what it was for YEARS. Lol. According to our book "EE" code means "Abnormality in controller power source system or communication system". Basically the controller maybe bad. I have trouble condemning the controller on one test!
Mine is just really weird because it was working perfectly fine I got out of the machine got back in and then it would not work
Did you find out what was wrong?
Yes, the controller must be bad. But it is to expensive to replace, $7000.00 for the controller and the machine sells for about $15000.00. I would like to know if it can be bypassed, without losing all safeties? I have tested all switches, sensors, wires, opens, shorts and grounds. Seems that there is no test for the controller. If all checks out OK then it's bad.
Where is the controller? Are you saying the swing brake controller?
No the controller is behind the seat, the seat must be removed to get to the controller. It has a digital read out on it. If yours is like ours and you have a 'EE' code on the console the read out on the controller will be blank or have numbers like 3.6..
Okay so today I tried to bypass everything I cut and spliced the red wire that goes to the solenoid I had power going to it and I had a ground going to it but I did not have control of my sticks so I connected the 24 volt power from the switch by the key and I disconnected the wire from that switch the permanent wire I had power going to the solenoid and I had it connected so that it would back feed the system and I did not have power going to
I have a PC75uu-1
We have a PC75uu-2. So yours does not have a controller behind the seat?
Ahhhh Ok different animal
I do have the uu-2. 5115 serial number. I was wrong.
If you have the "EE" code on the controller then something has been bypassed. Do you have a cancel/bypass switch on the right side of the seat mount? I have the wiring diagram for that machine and it shows that switch. Maybe the way it was bypassed at the switch came apart. I'm not sure how you could hydraulically bypass the safeties.
I do have the switch on the side of the seat I called come out to give them my serial number and everything and they sent me out the Hydraulic diagram and the electrical diagram for the machine I am actually working my way through the massive amounts of wires on the schematic right now trying to figure out where that switch goes
What's the part number for the controller ? I have found many on eBay for 300 up to 2000.
I don't know if I am wrong in my thinking but even if the controller went bad with the bypass switch shouldn't it still get the power 2 the solenoids to allow you to use your Hydraulic ? I have been looking at the wiring schematics and have not figured out yet what my problem is but if the controller is bad isn't that why they have the bypass switch?
Yes, but if your safety is already bypassed ( because of the preexisting "EE" code) then that must be where you problem is( your safety was already bypassed before you got your machine maybe). From what I see if you had a "EE" code before and it worked and now it does not, and the safety does not help now somehow the bypass loss connection?. Ours only works when you activate the safety. We have to jump the connection to the safety to make the controls work till we find a better solution.
My safety is a toggle switch. Isn't know if that's a factory thing or if that's how they bypassed it. I am doing a few more tests to see if the ppc solenoid is bad or if it's a food. I hope to resolve this soon
Ours is a monetary type toggle switch. With 2 wires on it.
Is there a test for the solenoid? I have power to the solenoid but no action
Power to one side and ground to the other, it should make a movement (click) sound. The solenoid should have resistance, when ohmed. The valve could be stuck or solenoid opened.
I figured out my problem. I had the power going to the solenoid. But no controls. Turns out the valve was not being moved. Took it apart and now the solenoid moves the valve and I have my controls back.
I got everything working but 3 movements the up, curl in, and the zero back .
Sorry and Yes it is a grey market. I have looked every where and can NOT find a wiring diagram.
Can you tell me where that valve is on a EX55.