Transmission swap reprogram computer?

Hi everyone, I recently swapped a 97 aw4 and np 242 in to a 2000 2wd xj. Basically did a 4wd conversion. The 97 transmission has an output shaft speed sensor, and the original 2000 also had an output shaft speed sensor but also had an input shaft speed sensor. So I swapped the 97 tcm in to the 2000 xj as well.

I now have a code of P0700 and P0720 which is output speed sensor. The sensor is good because I drove the 97 xj when everything was in it. So I'm at a wall here where I'm not sure what to do.

I drove the jeep to a trusted garage and we drive the jeep down the road with the computer attached to it, and the mechanic said it appears that the pcm and tcm are not communicating with each other properly. The scanner was getting readings like saying the engine was at 64 Rpm while driving.

So my question is would it be possible for me to take the jeep to the dealer or a tuner and get the pcm programmed to communicate with the tcm properly? I don't know enough about this to know what to do. Any help would be appreciated. Thanks!

2000 m.y. output speed sensor uses a different signal. IIRC you have to swap the tone wheel and sensor from the 2000 into the 97 trans

And to answer your question further.. The pcm and TCM are not custom tunable

Take the speedo assembly out of your old transfer case and move it to the new one

I swapped out the speedo sensor and it didn't fix the issue. I believe you're talking about the vss (vehicle speed sensor) but the sensor throwing the code is the OSS (output speed sensor).

Thanks for the reply digger. This has been a headache for me and I'm tempted to just find a 98+ aw4 and swap it in and go back to factory. More money and work but may be happy I did it. The OSS sensor isn't interchangeable between the 97 and 2000. So I can't really swap them over without probably machining on the transmission case.

Since the tcm and pcm aren't tunable I might be up the creek. I've heard of others doing this swap but not sure what else was involved to keep the cel off...

Ah sorry, misread

Isn't the TCM part of the PCM in 2000? IIRC, it is.

Yep you're going to need a later model trans.

Actually the tcm is under the dash on drivers side. I swapped it with the 97 tcm. I called a guy tonight and he has a transmission and np231 t-case with 138k from a wrecked 2000 xj he is asking $400 for the pair, but I may be able to get the transmission only for cheaper. I was hoping I could get the 97 transmission to work, but I'm tired of racking my brain over it and am ready to move on to something else more interesting like fabing recovery points and stuff like that. Lol

Ok, when you swapping in the 97 tcm, what exactly did you do? the 97 tcm has a slightly different connector than the 98-01 tcms. Also what is the part number of the 00 tcm and the 97 tcm?

you should have no issues with a 97 tcm talking to an 00 computer as they both talk over the CCD bus, now if you managed to get one of the wires hooked up wrong when you swapped it over that could cause the issue you are talking about.

All I did when swapping the tcm was shave the little plastic lip off of the harness part so it would plug in to the 97 tcm. Then I took the transmission harness and any sensors that wouldn't directly swap from the 2000 tranny to the 97 I spliced them in and just marched the wires up. I took my time and made sure I didn't mix any wires up

As for the part numbers, the 2000 is 56041386ab AN312663 00c

The 97 is 56027951 ak063089 97b

You need to get a 97 engine PCM. The 97 and 2000 TCM send slightly different messages on the CCD bus.

Know that a change was made in 98

Thought about is a bit more.

Might not work with the 97 PCM, also have to change the oil pressure sensor and it only supports 2 O2 sensors.

You could install a a 2000 PCM for a manual transmission. Cut the ccd wires from the TCM and install a connector to be used when pulling transmission codes. This will prevent the TCM from setting the P0700 fault in the PCM

Seems as the TCM doesn't need any CCD messages from the PCM to works properly. This type of installation is quite often done for AW4 swaps in TJ's

Still, you have to figure out why it sets the p720code