Ok that explains it! My harness is for the 42rle, and the po put a 32rh in! it has the 2 wire torque converter lockup plug and the 3 wire nss plug! What would I need to do to run the 32rh?
I've re-written this response multiple times as I think of different things.
I think we need to establish what computer you have. And then somebody with more knowledge than me on the 42RLE will know how to tell if the TCM is in the PCM or an external unit. Because if you have a computer trying to control a 42RLE but you have a 32RH, I would expect that the computer is going to bark at you. IDK if there is any bite to go along with that bark.
Now the 32RH doesn't need much from the computer. I'm ashamed to admit that I don't off the top of my head know if the NSS goes through the computer, so that will need to be handled, but if your jeep currently starts up then it sounds like that's already handled. The torque converter clutch lockup solenoid (aka TCC) definitely goes through the computer, but it's not absolutely necessary but it will throw a CEL and it could run hotter at cruising speeds. Theoretically you could wire it up manually if we couldn't figure out how to make it work with the existing wiring.
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But NONE of this has anything to do with your 32RH not shifting out of 1st gear since there is no computer controlling the shifts on the 32RH. There are some pressure adjustments & throttle cable adjustments (assuming you even have those in this Frankenstein setup. And those will typically result in a very very early shift to 2nd, not a missing shift to 2nd.
On the 32RH when it wants to shift to 2nd what happens is the intermediate (aka kickdown) band grabs onto the direct drum and holds it stationary. If that band can't hold the drum for some reason, then the transmission will
think it's in 2nd gear but will drive as if its still in 1st gear. The 32RH is a great transmission but it is D-U-M-B. If you continue to wind things up in this scenario, eventually it will say "ok 2nd gear is done, time for 3rd gear" and it will release the kickdown band and apply the remaining set of clutches to get 3rd gear and all is right with the world. This is precisely what sent me down the path of learning about the 32RH in the first place. My kickdown band spit the bit and resulted in everything you just read.
The kickdown band not being able to hold the drum could be the result of a few things. Easiest thing is that it's not adjusted properly. This can be done w/o even opening up the transmission; there is a bolt on the side of the case, and the FSM details this process. It could be that the band is shot, as was my case. And then it could be something more complicated like a blown piston seal or other pressure problem that's causing it to not apply. Many of those causes are fairly easily solvable, although if that band is shot the transmission is going to have to come down & get opened up. Happy to walk you through that.
What to do next? Hard to say. I would probably do the band adjustment before I did anything else. The FSM details some pressure tests you can do with the jeep on jack stands, but I've never done any of those. One day soon, though, probably.
I'm going to have to do some additional reading, because I opened up the FSM for the 2002 to review the pressure test procedure, and it makes mention of using a DRB scan tool for transmission codes and also makes a mention of 4th gear on page 21-226, so I need to figure out if that's just a typo or what.
p.s. I wish I knew more about this transmission, because any question you ask about the 32RH on google returns 2 pages of content authored by yours truly. I don't have anywhere to go when
I have questions.