General Confusion

I have (I think) a problem with my Transmission Control Unit (TCU)

The unit is an AISIN AW unit and is mounted under the dash on the passenger side. This unit controls the gear changes on the AW4 box on my 96 XJ.

The unit has the following numbers on it:

56041017 12V
AJ013980 96A

it also has a socket on it with the number: AJ6100082

I can find plenty of this units at salvage yards, but none of them have the same numbers on them. Can anyone tell me if I have to replace the unit with one with the same number on it, or is it just a manufacturers batch code or something.

McRay

What problem are you having - it might be one of the solenoids bad in transmission. Some shifting problems are cause bad connections or solenoid.

General Confusion

The problem is slow shifts up from 2-3.

The engine reaches 3500-4000 rpm before it shifts. If you ease off the gas at about 300rpm it shifts up. All other shifts up and down are fine. You can hear the TCU clicking while it is waiting to shift up to 3.

This was not a problem before, but I have just fitted 31" tyres which is making the problem a bit worse because of the change in shift patterns now.

bart

I have one you can try...........

Oh, you already knew that

The one in my othe breaker had a different set of numbers, again

General Confusion

Fancy seeing you here

I met up with J99P today and he has a 96 scrapper that he is going to check for me.

William Smith

Hello,

I have a issue with my 1987 Jeep Cherokee 4x4 select track auto trans slipping out of drive while I'm already up to 25 miles an hour or more.

If I remove the fuse from under the passengers side dash that I believe controls the sensors that auto shift my Jeep; I can manually shift my Jeep okay.

I'm trying to figure out what would be the most logical place to start trouble shooting this problem so I don't throw a bunch of money at parts I may not need.

Any ideas out there?

89floridaxj

im having a similar problem with my 89 xj. its a automatic 2wd and basically when i put it in drive it takes off in 4th gear... i have to manually shift it from 1-2 to 3 to D. it works fine that way but when i try taking off in D it just wont pickup speed because its in such a high gear. i took it to a shop today but they couldnt figure out how to hook it up to read the codes. they said its got 2 computers i need to have checked but im going to assume hes talking about the transmission control unit and the tps. any ideas? im thinking about starting with the tps since its the cheaper of the two but anyone think it could be something else? the fluids good and not burnt. i have no leaking pan. it shifts great when i manually shift

cdeal28078

I was having trouble with my 90 Cherokee not shifting at all. I was told to remove the transmission PC and try shifting it manually. If it would shift then the Throttle position sensor was bad. Worked for me. Seems the TPS has a lot to do with how and when the transmission shifts on these Jeeps
clint

89floridaxj

this may be a stupid question then but when you say tps do you mean the actual tps on the throttle body or is there a seperate tps for the transmission? this is my first jeep i was more of a chevy guy but im getting into jeeps and this is the first problem i have with it and im a little clueless with these engines

William Smith

Hey,
I asked around on this site for ideas about why my Jeep wouldn't accelerate unless I removed the TCU fuse under the dash that controls communication between the TPS under the hood and the main computer module.
I went ahead and replaced servos inside the transmission and that did not work.
I also replaced the TPS and that didn't work.
We also took a TCU module from under the passengers side dash and replaced it temporarily for about 2 days with one from a friends Jeep and that didn't work.

caged

general, yes, any from 91 to 96 should work.

89florida, yes, the tps on the throttle body. replace that and that should cure your problem.

will smith, i'm confused, you said that your slow take off problem is solved, but your post says it's not.
i would change out the tranny/torque converter and tcu, all from the same doner jeep.

General Confusion

I changed TCU (I managed to find one with the same part/unit numbers on it)

It made absolutely no difference whatsoever. I still have the same problem.

Having said that, I have just completed a 3300 mile Charity Rally across Europe, including driving through the Bavarian Alps and the truck never missed a beat, so perhaps I'll just live with it

mycherokee

You are having a TCM problem for sure. The way I know is I removed my dash to install a heater core in teh winter and never installed the lower half and I had to drive it the same way. Once I installed the lower portion it shifted automatically. You need to check and ensure your TCM is hooked up and check fuses.

89floridaxj

so you think its my tcm? thats what i thought at first because my check engine light is not on. with previous experiences when the tps goes bad the check engine light comes on and it runs rough but i thought i'd try replacing that first since its cheaper plus i cant find a tcm anywhere in the junkyards around here

frhrwa

I realize this is an old posting, but.... my sisters '96 Cherokee Sport has a major tranny problem.. its 4.0L auto.. the trans will suddenly lose OD, 3rd, 2nd.. and when your slow enough it will be in first.. other times, it loses just OD, sometimes it gives a bump type slip in any gear.. sometimes you have to shift 1st, second, third.. checked the fuse, power is good full time, replaced the solenoids, replaced the TCU and TPS, two tranny shops went completely through the trans and said it was perfect, clean as a whistle, absolutely NO problems in it.. so... ?