another question....
what brand of controllers are on it?
are they curtis?
sepex maybe? 2 1243's or 1244's for drive amps with a 1310 (or maybe a 1352eXM) main controller labeled as a lift amp?

Just guessing ;o)

Is there any switches on the mast? Possibly a speed limit switch for when elevated (or it thinks it's elevated)?

Yeah,it says lift amplifier right on it and the truck has no contactors other than a line contactor..but where the two pots connect is a little sticker that says electronic steering,wondering if maybe a part of that controls the steering.This is one of those jobs that you kinda wish the work order never hit your hands.

ok that small pot is the steering encoder and from the sounds of it it is working
the encoder(as you describe it) on the tiller is probably what yale calls a tach generator, they used those on thier orderpickers also.

inputs from both go into the lift amp? are you sure its a lift amp? and not a steering controller?

As for any supplements? no i do not have any, this model sounds like a new and improved version they designed themselves after the "schaeff" version that had at first when that model first came out.

I'll check around and see if i can come up with anything, or maybe someone else can jump in here and help? guys?

There is a small pot on the large drive gear indicating the position of the steer wheel.The tiller is actually a large encoder itself.Im wondering if it isnt the lift amplifier as the inputs from both go into it as well.I dont have the supplement for electronic steering,do you?

ray,

can you see any encoders on the steering assy anywhere?
or any sensors?
something is tracking where the wheel is positioned and may have an issue. bad sensor maybe? or bad encoder? usually you will get an error code if one of these goes bad , unless there is a mechanical problem with how it connects.

It does it in both directions,I have yet to see any codes pop up when the speed is reduced.Dont really want to start poking around without any info.The manual I have for the unit only goes into the hydraulic type steering not full electric.

if i'm not mistaken this is yales standup version?
mfg'd by schaeff with a yale sticker slapped on it?
are there any codes popping up on the display when you turn the tiller and it goes into slow mode?

does it do this in either direction of steering? both directions? or just one way?