Genie TMZ-50/30 Man lift with no power

[Snype32]

I am working on a Genie TMZ lift and am having a strange problem. I cant get it to turn on. Batteries are good, e-stops pulled, and I have 24v to the connector board and cpu board. But no lights on the boards. Any ideas where to start? Thanks!

 

[Jeff14889]

Go to genie website and download the service manual for it. Make sure you have power in and out of the key switch, and both e-stops.

 

[Snype32]

Thanks for the reply. I have 24v at the ground control box e stop. Haven't checked at the basket controls as I didn't think that would be a concern at this point. I have no power at the key switch.

 

[Snype32]

Just an update. Tested and found power at the basket e-stop switch. Definitely no power at the key switch tho. I tested using the ground point on the cpu board to the 4 terminals at the key switch. Nothing there.

 

[Jeff14889]

Usually all genies need to see both e-stops on the power up, no matter which controls your going to use. Really need the service manual cause depending on what the serial number is the wiring can be different. Looks like most of them the key switch is fed power from the ground e-stop.
https://www.genielift.com/en/support/manuals
follow that link to find the corrEtc manual.

 

[Snype32]

Thanks for the reply. I have been looking over the service manual. This is a DC model. The key switch just plugs into the same board as the e-stop. The schematic doesn't show what feeds it or where it goes. At a bit of a loss as what to do next. I don't imagine that even if a issue was happening with a limit switch somewhere that I would not at least get a light on either of the boards when turned on. I'm starting to wonder if the board itself is the problem.

 

[Txhayseed]

Whats your serial number and what color is your board ?

 

[Snype32]

Serial number is 5003-200

Boards are blue.

Thanks!

 

[Txhayseed]

You dont have any error codes before ? When did it work last ? Did anyone change any components previous to it failing to operate ? Do you have power to the circuit breaker and power going out ? As jeff said on genies power goes to the circuit breaker to the ground estop to the basket e stop then back to the ground to power up. So you said you got power to the platform estop, with they key switch in ground or platform mode ?

 

[Snype32]

No error codes at all. The display won't even come on. I'm working on this for someone else, so not sure when it worked last. I was told it was working fine, then was turned of, and never turned on again. The power is at both e-stops regardless of key position. But I am curious if I would be able to decipher where the power is supposed to come back to. I wonder if its possible that its not making the return trip properly.

Thanks!

 

[Txhayseed]

That is possible. The harness are susceptible to getting damaged. I had a jlg towable kick my but once. They dropped a hot welding rod and it melted a small hole into the harness inside the cat track and would only act up just in the right spot. You can ohm out your harness and give it the wiggle visual test. Are your dip switches set correctly ? The boards do fail..thats where the color comes in..the new " better" boards are blue..it is entirely possible you got a bad board. But if it " worked " and all they did was power down id be more to suspect a wiring issue first. I would run that down first to eliminate that before going to the board.

 

[Snype32]

Where do I ohm it out? Am I mostly looking for the limit sw circuits at this point? Dips are correct. Is there a document somewhere that indicates what should have 24v on it? I find it curious that if a wiring issue was present that it would cause this issue. Do all limits need to be closed for the boards to power on? I would assume that it should still turn on, but throw a code if there was an issue. Hopefully this makes sense.

Thanks!

 

[Snype32]

Tracing the three main limit switches was easier than expected. That seems to be fine.

 

[Snype32]

ok, so another update. I traced the e-stop circuit and ended up finding a broken pin in the connector for the basket controls. I plugged the basket control directly into the lower control box, so bypassing the boom harness. It now turns on! However, there are now a ton of coil faults that show up on the display now. Is there a single cause that would do that?

Thanks!

 

[Snype32]

So I'm wondering about something. I made a list of the codes... Every one indicates an open coil. So I'm thinking possibly a ground issue. Looks like there are two... Group a and b. So far they look ok, but I will look into them further. I was also noticing that the coils are labeled 20V dc. So I'm wondering if that is 20V max, and they should be getting 12v? or the full 24? There is a dip switch to select. Its currently set for 24, but it could have been messed with. Sounds like somebody else did look at it before me.

Thanks!

 

[Txhayseed]

Sounds like your on the right track. Ohm out the coils, if the coils are good your thinking about bad grounds is probably correct. You should be getting 24v at the coils.

 

[Snype32]

Ok will do. The harness looks to be good so far. I'll ohm out the coils. Kinda hard to believe that almost all of them would be toast. Is there a way to confirm the ground on the connector board is good?

Thanks!

 

[Txhayseed]

Back track your grounds to the main battery ground.

 

[Snype32]

so I ohmed out the coils. All seems good there. around 26 ohms
Grounds checked out too.

Not sure what to look at next

 

[Snype32]

One other curiosity I have found. I propped up the outrigger feet so that the switches are on, so the unit thinks they are down. When I switch it over to the basket controls, everything seems to work. The unit is in my shop, so I cant move it far, but it all moves. So I would assume that rules out the solenoid coils? It still flashes all the same codes.