Tower works up and down from ground. In platform mode, it will only come down. Will not go up from platform. All other functions are ok. Any ideas as to the problem? Tobias
I would check the output on the boom joystick when you try to rise it. If it will go down, the joystick is probable getting the input that it needs. You should be able to download a service manual from JLG's website. It will have wiring diagrams in it to help you identify the correct wires. Post the serial number and tell us if their is anything that you have already checked.
450A-#0300061648 w/ Deutz engine. I have repair manual w/wiring diagrams. I printed and enlarged them so easier for old eyes to read. Last summer/fall I replaced the hoses from the valve block up to the platform. And yes, it took me 2 months. When finished all functions at ground and platform worked accordingly. From then till now every week or so I would start it, exercise the controls and drive it around. All went well untill I actually needed it for a project. First thing I did was swap the plug from the tower switch to the platform rotate switch. From the rotate switch, tower went down ok, up was a no go. They are back in original position now. I pulled the red/bn tower up wire from screw #37 and checked voltage with switch engaged, no voltage. I am calling these wires 37 & 38 as I do not see any other numbers on the wire. Did same with blue/bn wire at 38, have 12.1 volts. Pulled canon plug from under platform console, checked continuity from socket N (red/bn) to end of wire at 37, no continuity. Checked blue/bn from P to 38, it has continuity. Looks like a problem with 37 wire. Next step is to break apart plug along side main boom and check the two wires in both direction. Make sense? I am thinking if there is voltage on the 38 wire, there should be voltage on the 37 wire. If you are wondering how I know it goes down without getting it to go up, I run it up a bit from the ground and hop in basket. Hope this has enough clarity to understand. I have tractors from 1947-1995. Them I understand and can sort out. This thing gives me a headache. Thank you for taking a look at this Tobias
It sounds like you're describing an analog model, later model JLG units have a computer at the platform and use CanBus communication between upper and lower. On the analog models, each function has its own wire going down the boom to the lower. If this is correct, and it sounds like you're describing tower is operated by a toggle switch, not a proportional controller, then yes, up has a wire going to the lower that should have voltage when selected and so should down. Again, if I've got this correct, it's a very common problem for the wires in the cable to break after many hours of service, especially where the cable goes through the power track on the boom extension section. After many cycles of boom in/out it flexes and breaks the copper wire inside a conductor, dead wire. If that's what's happened, JLG machines typically have a couple of "spare wires" that are not being used, and you can use one of those spare wires to jump around a broken wire. But that's just a temporary remedy. If you have a broken wire, won't be long until you have more.
Yes, this is a 2001 with the toggle switches. My bad for not passing that on. I had read about the spares in a post but forgot. Thanks for jogging my memory. For my machine, I am seeing H,M,U,V, R as spares in this cable. Next step will be to "ring" those out to make sure they are ok. It might take me a couple days till I get to it but will report back. Thank you Willie for pointing me in the right direction.
I hope that gives you a fix. But again, if it is a broken wire the fix will be temporary and no one knows how long it will last. If you have one broken wires, others are soon to follow. And in the future if you have to replace that boom cable, be sure and use OEM JLG. First of all, the cable they use is made for constant flexing where typical cable, like tray cable, is not. Second, you'll be working with the proper wire colors or numbers marked on the wires that match your schematics