JLG 40HA should I buy? Fixer-upper

[willie59]

Huh! never seen one that didnt have the joystick for the boom up and down

Yep, they made some like that.

 

[razerface]

ATCOEQUIP, great pics! That looks like my pump, (from memory). That helps a lot! What should those wires output measure when the PQ is activated? 12 volts? I will email my friend where the machine is,,,he'll want to test that today. The maint book doesn't have any good pics in it ( I can read though,,before you guys start on me!)

barklee, thanks for that generous offer! That could really help. We have been looking around for one to substitute and try. I live at Indian Lake, and travel to dayton every day. Are you local? I wish it had 2 PQ's too. It sure would be easier to diagnose!



on edit,, I reread ATCOEQUIP comments on PQ controllers, PWM outputs,, no testing of the PQ for the masses? Barklee, how can I get you a ups label? Would you like my UPS account #? I understand you are not sure if yours works either,,correct?

2nd edit, I found my camera this weekend,,,(we just moved). I can start showing pics soon.

 

[willie59]

The basic way that Pulse Width Modulation works is that the controller sends a voltage signal to either a solenoid valve (as with boom functions on a machine) or to the drive pump servo (like on your machine), but the signal is not a constant voltage, it's a pulse of full voltage followed by a period of time of no voltage, then back to full voltage, then none again. This happens in a span of milliseconds. A short pulse of on/off voltage just slightly makes the solenoid coil or servo react resulting in a low speed of the function being operated. A longer pulse of on/off voltage makes the unit react farther resulting in a faster speed of the function. By varying the pulse time you achieve proportional operation of the unit. The point is, there should be voltage on the colored wires of the servo harness plug, but you won't be able to read the pulse with a multitester, have to use an osciloscope to do that. But you might try and see if voltage is on the wires when you stroke controller. Also check that the brown wires are going to ground/earth.

 

[razerface]

well,,,,I think I actually understood that, thanks. I will check the voltage at the servo and work back toward the controller from there. That's what I needed, a place to start. Would it be better to try an analog instead of digital meter to see this?

so checking my new found knowledge... if the voltage from the controller was replaced with constant voltage,, it would drive as fast as possible, correct? Does the "off" time remain constant and only the "on" time vary?

 

[willie59]

well,,,,I think I actually understood that, thanks. I will check the voltage at the servo and work back toward the controller from there. That's what I needed, a place to start.

so checking my new found knowledge... if the voltage from the controller was replaced with constant voltage,, it would drive as fast as possible, correct?

Yep, it would work full tilt. But, your brakes would still be engaged. This is something I've never done before. I'm like Barklee and have an old PQ controller that I know works. If that don't do the trick, I start going through the system.

 

[Go2ndAmend]

I bought a used JLG 40H 4x4 at an auction 2 years ago. It was a 2006 model with around 1900 hours. I used it to build my shop since I really didn't have much help available and the shop has 18' walls. It saved a lot of ladder work and has been a wonderful machine. The only problems I have had with it have been a few electrical ones which my brother and I were able to fix.

 

[razerface]

how do I tell which PQ controllers will interchange? Are there similar ones that would work to test or to use?

My p/n is 1600116 in the parts manual, but we can tell that some other part has been substituted. When you look at it from the inside of the box,,you can see where the original holes do not line up with the current controller. I cannot decide what the p/n is of the current controller. How to tell?

 

[razerface]

I called Hindley about the controller with their name on it. They say that number is a serial number,,and it tells them they rebuilt that controller in 2005, and it is the correct p/n for my machine.

 

[willie59]

I called Hindley about the controller with their name on it. They say that number is a serial number,,and it tells them they rebuilt that controller in 2005, and it is the correct p/n for my machine.

Well, all I can say is Hindley knows those components. If they say it's the correct controller, I would tend to agree with them.

Did you check that you have power on pin #3 (yellow wire) of controller harness when footswitch is depressed? Did you check to see if you have a voltage output when you stroke contoller on pin #5 and #6 (brn/red - brn/blu)?

 

[razerface]

Did you check that you have power on pin #3 (yellow wire) of controller harness when footswitch is depressed? Did you check to see if you have a voltage output when you stroke contoller on pin #5 and #6 (brn/red - brn/blu)?

I checked the wires at the other end (solenoid) last night and got nothing. I got called away and did not get to keep checking stuff. My plan was to work from the pump back toward the controller.

I am impatient to get some time working on it. As soon as I start, something else comes up and drags me away. Last night my bobcat started dumping fuel on the ground. I had to go,,,,,

I have a question. Remember I am not an electrical guy! On the diagrams for the platform and main,,it does not show where the wires go from the numbered terminal blocks. So, does #3 on the main, go straight to #3 on the platform, 4 to 4,,ect, ect? There is just a wire harness connecting the 2 places using those numbered terminals at each end of the harness?

Then for example, on the platform diagram, from switches, instead of drawing the line to the numbered terminal, they just number the end of the line. Am I looking at this correctly?

 

[willie59]

No worries, we'll work through this. Actually, I start at platform end on something like this, starting with controller, then start checking wiring, as these are the most common things that cause problems. JLG diagrams can be a bit of a challenge to read. I'll work you through a couple of circuits so you can get a handle on how they work.

Open the parts book PDF you downloaded from the website, go to page 7-10, Figure 7-5 Platform Electrical Diagram-Bang (Standard) Controls. That's your machine. You might want to rotate the view clockwise so you ain't looking at it sideways, that drives me crazy. :tong

Look to the right on the diagram (not box at far right, that's 4 wheel steer, not yours) and you'll see a small box that has Drive above it. That's the connector in the PQ controller harness, has 9 pins in the connector. Just below that is a column that say "Pin" and numbers 1 - 9, that's the wiring of the contoller harness, corresponds with the pins of the connector. Pin 1 brown is ground. Pin 2 blk/orn has a square box at the end of the wire with number 22 in the box. That means that wire goes to terminal 22 of terminal strip at bottom of page. If you look at terminal 22, you'll see it's Brake Valve, meaning that circuit is the circuit that releases the brake when you operate drive. Pin 3 yellow wire has a box with #35 in box, that goes to terminal 35. Terminals 35 - 39 are 12V when footswitch depressed, so that would be the wire that sends power to the PQ controller. Pin 5 brn/red has a box with #16, this goes to terminal 16 of terminal strip, you'll notice that is Drive Reverse. Notice the brn/red wire leaves the opposite side of terminal strip and continues in the 16-30 control cable going to the lower main control box.

Now, go to page 7-12, Figure 7-7 Standard Electrical Diagram - Deutz With Standard Bang-Controls, again, your machine. With view rotated, you'll see the 16-30 cable from platform to the left of page, and the brn/red wire with a #16 box, that means it connects to terminal 16 of terminal strip. Now, you're going to ask "well, what else connects to terminal 16, it doesn't show anything at the terminal?". Yep, that's where JLG diagrams are tricky. Look all around the page and look for any wire/connection with a box that has #16 in the box. You will only find one, at the right top of the page you'll see six brown wires (grounds), just below them you'll see 35 yellow, 13 blu/red, 21 brn/blu, and your 16 brn/red that your looking for. This is the wiring harness that goes to machine lower components and engine compartment.

Go to next page, 7-13, that's the lower harness that goes with your diagram. Again, with view rotated clockwise, to the right of the page you'll find the brn/red wire going to pin b, that's the connector for the harness at the drive pump. There ya go, you have just traced through the drive reverse circuit.

 

[razerface]

ok thanks! I was sort of seeing how to do it, but got lost on the lower harness jump. My diagram does not tell me that is the lower harness on the right.

I resized the platform and main schematics to 2 or 3 times bigger,so I can read them,,printed them in sections,,,taped back together and laminated them for protection. I am ready to get greasy this weekend!

I guess I need to also do the lower harness.

Thanks alot for the lesson,,I feel like I know how to do this now, at least the simple circuits. I'll report back this weekend with what I find. Actually get to work on it some friday I think. I have all the manuals printed and in notebooks,,,I'm ready to find out my "electrical detective" capabilities.

What is R1,, R2,,, ect,,coming off the control switches and other places on the ground panel?

 

[razerface]

I forgot one of my questions. Can I do this work without the engine running? Since I am trying to get thr drive working,,I may have to tape the controller in position and put a weight on the footswitch for some of my tests. I don't want to get run over, so,,,everything will still react the same without engine and pumps running?

 

[willie59]

What is R1,, R2,,, ect,,coming off the control switches and other places on the ground panel?

Ahh grasshopper, you noticed those oval symbols with R and numbers in them. Perceptive.

These are connections to Relays (R) and the number is which relay, and the relay terminal connection. There are two types of relays in the lower control box. The black cube relays and the two (what we call) ice cube 14 terminal modular relays. On page 7-12, you'll see the ice cube relays 1 and 2 to the right of the terminal strip. If you look near bottom of page you'll see the switch for Tower Lift. Notice the red/orn wire coming off the tower lift switch going to two oval symbols, one R2 - 8, and another R2 - 7. This means that red/orn wire from tower lift switch goes to relay #2 - terminal 8 of relay, and to relay #2 - term 7 of relay.

Also, they represent connections to the black cube relays. Look to right of page at harness for lower components. Look at the red/orn wire for the bang bang dump valve, it has an oval symbol with R13 - 87. That would connect to bang bang dump relay 13 - terminal 87 of relay at top of page.

And yes, you can do most voltage tests with ignition on, engine not running, and footswitch depressed.

 

[razerface]

ahh grasshopper, you noticed those oval symbols with r and numbers in them. Perceptive.

thanks,, I have to go study some more now. It's not too bad after somebody explains it.

 

[willie59]

thanks,, I have to go study some more now. It's not too bad after somebody explains it.

Well, there's still some spots of JLG diagrams that present a challenge to me, and I've been looking at them for years.

 

[razerface]

well, I tested and found out reverse was no good in the controller. I got no voltage at controller or at the pump from the reverse leg. I already had Hindley send me a new one which I got today. It is different then the old one,,but it looks like everybody who drove this thing stopped and worked on the controller with their soldering iron! The new one is sealed.

With the new controller, we get a gradual 12 volt at each leg at the sunstrand valve,,but the lift still won't move. I know the voltage ramps up to 12v to increase speed. How do I test the sunstrand? It hummed a little,,but that was it. We took it apart but could not see anything obvious wrong.

 

[razerface]

after we got the sunstrand off,,,we noticed a small lever on top to manually work the valve. We did not put it back on to try because it is hard to get on and off. We want to test first.

This thing is hard to find in the parts manual. Still looking. Maybe it isn't a sunstrand just because the pump is? I am talking about the electric valve that the controller runs to drive the machine.

edit: just reread in post 23 that ATCOEQUIP calls it a "drive pump servo"

 

[willie59]

The drive pump is on page 2-78 of parts manual pdf. The component that has the screws #82 and #83 going into it is the servo for the drive pump. That's the component that the control harness connects to. Do you have the entire drive pump removed from the machine?

 

[razerface]

Do you have the entire drive pump removed from the machine?

no, just the servo