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@Roger_Roberts - it doesn't look like any work has ever been done and it's fairly clean in the compartment. Both C1 studs were internally connected, but I can see it would be easy to over torque and break. I'm hoping it's not the card because 1) used cards don't seem readily available, 2) I'd be taking a risk the card even works properly, and 3) new cards are ~$1600. Hoping 2 and 5 do the trick!

The #5 Rec charges the Capicator, and if it has any charge it is probably good. If it was weak it more likely would let you run with the wheels off of the ground but trip under loads. When the Cap goes bad usually it is leaking oil, or I have had the connection from the post to the material inside break as if someone turn the stud trying to get the nut off and it is just an open. I think twice out of hundreds of time it was the coil the one where the negative leads all tie to. It may also be the card is not turning on the 2 or 5 if the card is bad, the plug from the card to the 2 and 5 may have a bad connection. It this was worked on before you got there well then then there may be a wiring issue. As a matter of fact the older Hyster manuals show going to the mounting screw and not the terminal on one of the recs. But in my experenice >90% of the time changing the 2 and 5 and its working.

@liftero1 - good to know. I tested C1 by manually discharging and verifying a slow charge rate over a few minutes, rather than an immediate charge, the latter being indicative of a faulty capacitor. From what I can tell, C1 is working properly. If REC 2 and REC 5 don't fix the issue, I'll test C1 again. Any other testing methods for C1 I may have missed?

Still waiting on REC 2 and 5 to arrive for install.

As roger said it does sound like a pmt fault scr 1 on the ev100 is fairly bomb proof but changed plenty of rec 2 and rec 5 on ev100 panels probably the weakest point on it. Normally I find it's rec 5 that has failed. Another thing to check is the capacitor charging ok because I've changed a few that weren't supplying the correct block voltage causing a pmt

Thanks, again. I went ahead and ordered SCR 2 and 5, rather than testing the installed rectifiers. As far as the condition of everything goes, all looks good in the where the control card, relays, capacitor, rectifiers, etc. are located. A local shop wanted over $1K to replace the accelerator potentiometer and foot pedal microswitches, which I'd already tested. I replaced them anyway, considering them to be the experts. It obviously didn't fix it, but at least I got it done for $65 and not $1100. I'll update with results of replacing the SCR's once received.

Its called PMT (Pulse Monitor Trip) your #1 Rec is turning on but not off. Most of the time it is either the #2 or #5 Rec that is bad. Well as long as none of the wiring or the connector to back of the card is messed up. If you arn't sure which ones I am talking about I can send you a picture. They should cost you under $50 each and they are next to each other sometimes it is prudent to just change both out. When doing so you want to unplug the battery and there is a large capicator on the panel you want to short the 2 terminals on it out with a wrench or screw driver before messing with it. The #2 and #5 look the same, a black block about 1" x 1-1/2" with 2 screws and push on tab
The part numbers are #2 Hyster 368919, #5 Hyster 368918
I have a picture of them but I don't know how to send it on here.
They cause 90% of the #1 not turning off which is your problem

@Roger_Roberts - It jumps forward or reverse when the pedal is pushed but immediately, the contactor opens preventing it from moving further. I can't get it to move at all for a few minutes, even if I cycle the key switch. The hydraulics will continue to work, though.

@lifter01 - I'll see what I can do to test the SCR. If I recall correctly, I need a 6V signal to fully test. Yes, EV100 panel on this one. Thanks for the suggestion!

Sounds like an scr fault I've had a few issues with scr 5 failing causing the truck to jump. EV100 panel I take it??

I have a 70 in which I changed the tilt cylinders and went to start it up and got the fault code of 524251-1. So went to office and it was looked up as a 5V (OORsomething?) Pulled the trany dip stick and the oil was foamed, like fluffy foamed. But it was doing the same thing as in no backwards and forwards. On the top of the trany are the words "Hydro only" so I dumped in about half a gallon and was backing out the lift when it quit again, this time the fluid was less foamy but still had air in it.
In my case I am changing the filter and filling with JD40 as I think the iso fluid is not the one to use.
Funny thing is, is that this lift was used for days with no problem traveling and then I fix the tilt drift and poof there it sits.

Do you say it jumps forward or reverse, then the contactor drops out?
Then you can not do anything until you cycle the key switch