Hi, I have a Hitachi EX 135- UR excavator, which im having trouble with. The cab avoidance monitor, isn't working and is showing -E- on the screen, the boom arm won't raise, the dipper will raise but not lower. Slew and tracks work all ok as does the blade. There are no faults with the cab avoidance monitor ( according to the manual) as it shows no fault lights or beeps. All arms work when over-ride switch behind the seat is pressed, but not when over-ride under arm on right hand side is pressed, as this does nothing. Any ideas on what could be causing the problem?
Did you fix your problem? What was it as I appear to have the same issue. Thanks!!
Is this a offset boom? If it is check potentiometers and wires.
Yes it’s an offset boom. Wires appear to be ok without taking off covers to sensors. Your referring to the sensors correct? Thanks for your response!!
Need to take covers off check switch and wires.
I agree was just reading about testing the ohmeters. You help with that key word potentiometers. That’s not in my manual!! Thanks so much.
One more question. Should I start at the cab end or feed back from the digger end?
Bolts are on there super tight...oh boy...
Don’t think it makes any difference .I start at top.
Ok we believe we need to replace the arm sensor. Problem is the ones I see online do not have the correct fittings or screw holes etc. Are there conversion kits or something I am not aware of? Again...thanks for your time!!
Try dealer?
Check here
Yes that’s the part number but doesn’t look like that. Strange...got six bolt holes etc...parts catalog does not match the design. But thanks for your help.
They sometimes upgrade design when they have a problematic design.
It's likely a gray market machine.
Your probably right but I should be able to convert it somehow or purchase the part in another country. Can’t find this or a conversion kit so we are kind of stuck now trying to figure this out. Is there always 5 volts of power to all of those wires for each sensor or is there fluctuation based on throttle speed and what is turned on at the time of testing? What is the voltage we should see coming from the arm sensor? We tested the sensor and it appears like it is working but there is always the possibility of fault right?
When we test the sensor, the wiper function works perfectly. Thinking this sensor is good.
Bad connection?
Ok so we found another issue. We thoroughly checked the fuse box. We confirmed all fuses are ok and working. However, terminal 9 and 10 highlighted in the diagram above do not have any voltage on the terminal itself. They should be alive right?
I would probably guess that you are correct. Most of the fuse blocks on machines I've worked on used a simple buss bar to supply power to one side of the fuse. Can you take the whole block loose and check the back side of it or maybe see if there is a separate power source to run the two circuits?
All inward fuses connect to power as it says in the document and if you look at this diagram, the two cables from 9 and 10 connect together. We had it out temporarily and it looked good. Didn’t test it. Does the engine have to be running for it to be active? I didn’t think so because all the others work except glow plug which shouldn’t anyway.
Trying to iron out where 432 really goes.
Update...per the wiring chart, fuse 9 an 10 are powered by one cable that feeds from the alternator thru the icu relay (see wiring diagram attached) and then to the fuse and then split to power 9 and 10. We have jumped 8 to this power terminal and everything works without using the override switch. We tested the icu relay and terminals 1 and three are live but 5 is dead when we take out the jumper to 8. We even used two separate relays and got the same outcome. Which leads me to believe that the problem exist either with the wiring after the icu relay all the way to the fuse box or can it be the terminal itself is faulty in the fuse box. The wiring harnesses in this machine look really good so it really makes me wonder. Would it be a good test to run a wire from terminal 5 on the icu relay to the power terminal in the fuse box? Would this tell me the wiring from the relay to the fuse box is the problem if it works? I am looking for ideas because I am not sure what I should try next even though I have isolated the problem area....