try swapping forward and reverse valve with solenoid they should be the same.
same for the pressure transducers if problem shifts from reverse to forward you have got an answer.

mark

Will this kit on eBay take the proper measurements? http://www.ebay.com/itm/220981697550?ssPageName=STRK:MEBOFFX:IT&_trksid=p3984.m1432.l2649

Also FYI for you guys. This truck has over 6000 hours on it. If that changes any opinions

get a pressure guage and re-verify the tech's findings on the reverse clutch pack pressure
it could be something in the control valve blocking the fluid flow on the reverse side?
The pressure issue can cause the transducer to throw a signal triggering the code and lead you in the wrong direction.

with electrical over hydraulic controls its not hard to confuse issues and think it could be electrical ;o)

I wouldn't take the transmission out until you are sure you need to. You need to clear the codes and start over. Have everything hooked up and start it. Put it in forward and reverse and watch what code comes up and when. I don't understand how it can have no pressure to the reverse clutch and not make a code. That pressure switch senses that. If the solenoid is activated and the pressure switch doesn't sense pressure, a code will come up. And furthermore, the clutch piston would have to be broken if the solenoid is working ok and trying to pressurize the clutch pack but the pressure is zero. That seems unlikely. At any rate a code should appear.

Is there a rebuild kit with everything I need in it to rebuild the transmission or do I need the diagram? Do I replace just the reverse clutch pack or both? I would think replace both but I am trying not to assume anything.

I got the service ticket from the guy who had it looked at before me. Here is what the yale dealer ticket says. "4/15/13 Drove to location, located unit and troubleshot. Found code 524224-3" Then below that it says, "4/16/13 drove back to location installed used pressure transducer. No codes, only has forward. Checked reverse- no pressure to clutch packs. Needs trans rebuild"

I would want to try a "known good" reverse solenoid and valve. you won't find much you can work with in this steering col. and you can not swap dashboards from 1 truck to a different truck. the directional switch swaps out easily, but I would be truly shocked if it was the problem, as the signal from the switch goes to the computer before it turns on relays that turn on the solenoid.
You may as well get your local Yale dealer's tech to come out and reset the password so you can trouble shoot through the dash.
I would also suggest only the OEM (Hyster or Yale) replacement for this 'solenoid valve' not the ones from TVH, (and change the entire valve assy, not just the coil) just personal experience.

The steering column is a little shaky. Not too much but has a little side play. Any way a pinched wire causing any of this? Can I take it apart and have a gander without messing anything up?

The code does not come up if it just sits in neutral. When shifted into forward gear is when disable fault comes up. As of right now it will not move at all. It will not drive forward nor backwards. Two days ago it was driving forward fine and no reverse. I switched out the battery with a new fresh one and still have fault codes.

Sounds to me like the reverse solenoid coil or wiring to it is shorted. If you start and leave it in neutral does the code come up? Do you have to shift it in gear to get a code and see disabled? Does it go ok if you try going forward before trying reverse?

Coil Driver Output Out Of Range High:
523920-3 = REV1 Circuit Shorted High (Powershift Transmission Repair)
maybe a bad trans? maybe the coils in the valve?

Ok FYI truck disabled came up with fault 523920-3. Now it will not drive in forward or reverse. Should I call a tech or is this something I can do myself? Also, no new devices have been added. The two lights on the top have been unplugged.

522760-4 switched battery voltage out of range low.
has anyone added any devices to this truck that were not factory, like a scale, camera, b/u alarm or impact alarm?
this can be a bad relay or the relay box [Hyster calls it the power distribution box] itself, but in my experience, it is far more likely to be related to added items that were not properly wired into the system using the proper power supply taps supplied by the system.
since the error and failure is in reverse, I would first remove the backup alarm wiring.

We replaced the solenoid. Fault code 522760-4. If I can drive in forward gear do I still need a password?

you should not need a password to be able to see the error codes, it sounds to me like your trans (either the reverse clutch packs, or the control valve) is bad, but we would want to take pressure readings on the transmissions test ports to be sure.
you will be calling the local Yale Forklift dealer to get them to reset the password or give you a service level password anyway, might as well get them to check the trans.
as far as seeing the codes, watch the dash as soon as the error is happening.