Hi all, brand spanking new here, so HELLO! Got a tricky one that I haven't seen in the forum....
I have two 1995 xj's, one is in a very special condition, and the other not so much, For the one I'm keeping, at first I only had first gear, that's it. I replaced the TPS and topped off the fluid when I got it home. Then I get reverse and third gear - I could also manually shift from first on up to D. In drive, it would start out slow in 3rd gear - close to fixed, but no cigar. So, I drained the fluid, and replaced all three solenoids, and put fresh fluid in (at least the pan doesn't leak any more). NOW, I have reverse, and it won't go out of first gear in drive - won't even shift manually. Stays in first gear. (Caveat: I found the harness connectors in the transmission brittle and all three plastic parts fell out. The electrical connections seems firm, so I just zip tied them in). I didn't find a fuse near the TCM, but I did swap out the TCM with the other known good one - no change. It appears I traded one problem for another. Did I mess something up? I thought I'd ask before I have to tear into that pan again. Also, I didn't do anything special when I popped in the TPS, nor did I mess with it between the two different symptoms. I don't know what's left to check. Please, please advise!

 

Sounds like you did have a bad solenoid, and you fixed that. Try pulling the fuse for the TCM (should be in the fuse box, not inline like the older Cherokees) and see if you can shift manually again. Check the throttle-body to trans cable. Also inspect the wiring to the output shaft speed sensor in the rear of the trans - if that's messed up the TCM doesn't think you're moving and continues to command 1st gear.

 

Great leads! I will check all those things tomorrow. TCM fuse is under hood? Or under dash?

 

Under dash I believe

 

sure enough! I pulled #13 (it was a 1 amp) completely out and took it for a drive. Shifts fine now in D. So should I just leave it pulled? Just from eyeball, it looks like a good fuse (that, and that’s the only change I did and it fixed it). Begs the question, what do it do? Much much thanks!

 

I spoke entirely too soon. Took it out for another drive up the street. I can now manually shift it. That’s it. I’ll try putting the fuse back in and see what I get

 

So, I still have my problem. Sometimes it's fine, sometimes it stays in first gear, sometimes in third. It doesn't work manually when it's like this, unless it's in the "working fine" mode. Having difficulty having confidence in locating the correct TCM fuse. Either way, these symptons change without me doing anything. Now I'm thinking loose wire? weak relay? The symptoms don't seem to be changing WHILE the vehicle is on. It seems to change up after I turn it off, wait a few minutes, then go for another drive. Sometimes the next day. If anyone has any leads, please let me know, Thanks!

 

Tip 10. www.cruiser54.com.

 

I think the TCU fuse is shared with the PCM, but don't quote me on that. Best bet is pulling the TCM connector itself to verify manual shifting. Manual shifting means the shifter in (1-2) you get 1st gear, (3) third, (D) is 4th without lockup.

If reverse is not working, that's a mechanical problem and not and electrical/solenoid problem.

 

I would suggest taking it to a transmission shop that has the ability to hook into the TCU and "read" what it is doing. That will either diagnose an electrical issue (tcu/tps/soleniods) or a mechanical issue such as a faulty valve body or other issue. I chased a "ghost" inside my transmission for 6 months with no result.