I have a 2002 hitachi ex135ur-5 that won't throttle up. Worked fine then sat for a couple weeks and the problem started. The key will start the machine but has no effect from the on. It will only idle and they key will not shut it off. I have to use the manual emergency stop cable. I have another identical machine that does run so I've been switching parts but no luck. I have checked all the fuses, switched relays around, changed the computer, the step motor, the alternator, the key switch, the throttle control dial and pulled the main wiring harness connector behind the seat apart a die-electric greased it, along with greasing almost every other connector. I've checked the wiring harness for obvious damage except where it passes thru the firewall. I've never had to work this hard on a machine to get no results. I've run out of ideas and a few suggestions would be appreciated. If anyone has a wiring diagram I would be willing to purchase it.
what is your email address ? I can send you one .
[email protected] I really hate giving up and installing a manual throttle but this is getting frustrating. I had 6 of these units at one time and they are great machines. It could be just something like a spade fitting that has oxidized but I have jiggled and greased everything I can get to but no response so far. Today I will remove the seat base and look at the harness where it comes thru the firewall.
Also the throttle motor gives no response at all when the key is turned on or off even with the exchanged computer and stepper motor.
Have you checked the diodes behind the operator seat?
I have them exposed but I'm not sure how to test them. It's been so many years since I tested one of them I forgot how. Would they effect the power going to the controller?
You can check them with an ohm meter. There should be continuity with the leads touching one way and none if you reverse them.
Just a thought .Is the throttle cable free? ALSO CHECK THE THROTTLE POSITION SENSOR IN THE HOUSING.The gear maybe stripped
Learning switch positon ?
I swapped the diodes but no difference. A friend who gave up on his ex135 gave me his disk doctor but I'm not sure how to work it. I found a plug behind the left council (radio side) that says SMC on it but without the wiring diagram I'm not sure that's correct. When I plug in the dr ex it says it's not communicating. The program or model I select is (to30tKg5). Ver 1.07.
The -5 series uses a momentary toggle switch. You have to push and hold the switch to override the position sensors.
A member was kind enough to send me a manual but it's for a later zaxis model. The ex135ur-5 is a gray market machine so it is now impossible to get manuals from John Deere. I have the technical manual for older ex135ur but it is also different. I sure would appreciate it if someone has a manual or knows someone in Japan or Europe that can get ahold of one. Thanks
I have manuals here but i suspect their for an earlier model. I doubt they'll be far wrong though. Is there a learning switch and diag connector next to a fuse box behind the seat? Yoy meantion that you need to push and hold the learning switch to override the position sensors? There should also be a learning switch to perform engine learning. Basically this makes the stepper motor go to its min and max positions so the controller can remember where low and high idle is. Most Hitachi's from the ZX-1 and earlier have them. Make sure that's in the centre position, although if it wasn't, you'll hear the motor moving every time you turn the ign on. First off all i'd confirm whats actually happening down at the step motor wiring. The 4 pin plug is the motor plug. you have 2 positive and 2 gnd. If i remember correctly, looking in the 4 pin plug on the machine harness with the locking tab at the top, the top 2 pins are positive, the bottom 2 are ground. The 3 pin plug is the EC sensor. Pin 1 is a 5v feed, pin 2 is the signal wire and pin 3 is the gnd. With the ign on, make sure your getting a 5v feed and a good gnd. Then check the voltage at the signal wire. It should read around 2.5v if its in the idle position. If your getting that, check the 4 pin plug. With the engine running and the 4 pin plug plugged in, get some one inside the cab to turn the revs up and down. With a test lamp, ground onto pin 3 and check pin 1 for voltage, and again ground onto pin 4 and check the voltage at pin 2. This will confirm if the controller is sending the appropriate signals down to the motor. Once you know whats happening you can decide whether its an electrical issue or a component failure. Although with you having changed everything it does sound like a wiring issue but the earlier test only takes around 30 minutes so it's worth doing.
Thanks for the tips but I did install a working step motor and still no response. Since I used to have an older ex135 I still have the technical manual for it but the -5 is different. There is no learning switch under the right console like on the older one but has the single switch behind the seat. The second control unit is under the right console and I swapped that one also but I'm not sure how much the two controllers interact. These machines that have the offsetting booms have a system called the auto-marccino mode that stops all the hydraulic functions if you move the bucket into striking distance of the cab and I'm not sure how or if the two controllers interact. I've think I've swapped just about every component that would stop the machine from throttling up so I suspect it is a wiring harness problem. It appears in good shape but between the motor compartment and cab it dissapears into a tuff place to get to but I'll just keep taking stuff apart when I have time. Now I hope my other machine will run when I put it back together. I do have a Fluke volt ohm meter and have been checking the obvious things but I figured just swapping working components would be quicker.
member "excavator" referred me to "Tradebits" www.tradebits.com where I dl'd a manual for my Hitachi EX 60, this morning. I'd make the same referral. Without the manual, I'd be checking my battery voltage. The ECU needs proper voltage to tell the machine what to do. I had similar problem with mine early on, and it ended up being a toasted alternator, due to a failed relay for the intake heater. It was drawing massive amperage and took out the alternator. So, make sure your batteries are up, and then figure out why they're not, if that is indicated.
Did you ever figure this out? I am having the same issue with an ex150-5. Thanks
Mine ended up being a clogged screen, inside the banjo fitting, at the end of the fuel line from the tank, where it plugs in to the transfer pump. I had to take cover off the bottom of the machine (sitting down between tracks, and looking up). The rubber fuel line slips onto a hose clamp fitting on a banjo fitting, with the banjo bolt going up into the transfer pump. In there is a plastic screen, about finger diameter x 2", with probably 1/16" screening. Hope this is it, because it's an hour, at most, to fix.
Oh, sorry, that was a different issue, with my other EX-60. That said, I tried to buy a rebuilt from Napa, which was about $160 (instead of $750 from Deere). It came without the pigtail bullet connector. That connector has something to do with the shutdown process (slow discharge, rather than immediate off), which protects ECU. I ended up taking my original alternator to local rebuild shop, and back up and running for $89. I did have issues with my alternator in the other machine (that's why I know that the cost is $750), a long time ago. The relay that controls the intake heater stuck on, and fried my alternator. I was running machine, and then it just went to idle. All of the lights were on at the control panel buttons, but no response. I couldn't even shut down, as there wasn't enough voltage to energize that solenoid. This was in the payphone days, so I left machine run for about an hour, while I went to the nearest payphone, and called for advice. When I got back to machine, apparently there was enough surface charge on the machine to throttle up, get it on the trailer, and shut it down (needed to jump when I got to dealer for repair, though). $3000 later, they diagnosed problem, and replaced alternator and batteries (left the relay be, as I shut down for winter, and didn't want to spend another $400 for it). Too bad if this is your problem, as the fuel line screen would be much less expensive.
Thanks for the info grandpscott, I have seen the banjo fitting problem many times... this one is deffinatly an electrical problem. The machine controller does not seem to be putting out 5v. I bought a new controller but still nothing.
Johntims I gave up on my ex135-5 for now. Since I have two I have been busy using it here on my ranch. I had swapped both computers, alternator and stepper motor from the running second machine but nothing made a difference. The only manual available from Japan is in Japanese so not much help there. When I have time I will chase the wiring harness where it goes under the seat and disappears under the firewall. I'm not getting any voltage to the stepper motor and the harness appears to be good everywhere it's visible. Tracing it thru the frame is going to take some time and more disassembly. Alibaba.com has some manual throttle conversion kits listed for some Hitachis but none for mine. If your machine doesn't have the offsetting boom you really don't need the computer and you may want to go with a manual throttle.
Had a machine the we had the boom line bored once... when we got it back all seemed well until I tried to use it at night... then we noticed none of the lights worked and it kept blowing fuses, took a while tracing wires to determine the guy doing the line bore had lit a fire under the cab and burned some of the main harness that carries the light circuit and many others. So just thought I'd share our experience in case you have a similar issue going on.
Spica const. I got it figured today and judging by what you have said I’m pretty confident we are having the same problem. Mine was a bad arm roll in pressure sensor. It is located in the pilot manifold just behind and below the cab. Being that yours is a zero tail swing it may be in a slightly different location. There should be two sensors in the manifold. The one with 3 wires going to it will be the arm roll in. The other will only have two wires. Unplug that sensor, if it’s your problem the machine should function as normal other than a code for that sensor having an open. It is possible that it could be one of the other 5v sensors on the machine causing it. If the arm roll in doesn’t take care of it you may want to try some of the others. There aren’t many so it’s pretty easy to narrow down once you have it figured out. Just unplug them one at a time until your throttle comes back.
I'm going through the same on my zx 225uslc Machine won't respond to throttle dial. Machine won't turn off with key. I've replaced the throttle motor and didn't fix it. On the 3 pins ec sensor while running at idle I read 4.5v 1.7v and ground. Regardless of throttle position those readings don't change. I read your write up and also tested the 4 pins on the motor side and pin 1 is (. 2 to 1.4) fluctuating pin 2 is (. 2v) pin 3 is (. 5v) and 4tj is ground. Any insight would be amazing I'm pulling my hair out. I've done a relearn probably 8 times doesn't do a thing. Motor doesn't even make sound now when starting. Randomly will work fine one day then next no response.
I haven’t got mine figured out, I’m retired and have more than one so I just gave up for now. Alibaba has hydraulic retrofit kits for some Hitachi models but not the EX 135. It uses pilot control hydraulic pressure to actuate a motor that pulls on the the throttle cable. If there are kits available it must be a common problem.
hi.. hitachi EX135UR-5, error code display E18 & E50, what is it mean? please help me. Thank you
It’s grey market and will drive you nuts.We spent hours on just that problem and went to a cable.Job done.