95 XJ - Way to add comfort/power button for trans?

I am not sure that will work. I have a TCU from an 89 and replaced my 91 TCU for a day. Didn't work all that well. Switched it out as soon as I got home. It does work on my 90 though. How it is wired may be the same or nearly so but what about the circuitry? The PN's for the TCU are probably different.
 
This thread is old but since it was bumped by somebody else... the TCU uses signal from the TPS and other inputs to make decisions, so mixing TCUs across different generations TPS is unlikely to produce desired results. You'd have to replace the TPS and that would just cause other problems with the other systems that also read that data.
 
BTW the 91 HO had the Power/Comfort switch. You'll have to add wires and get a 91 TCM.

You could use a 87-90 TCM but you may have an issue with the TPS since the Rennix use a 2 sided TPS and the TCM powers the half it uses as opposed to the 91-up which splice into the engine (uses the 5V provided by the PCM) and use a single side TPS.

But as others have stated why bother really.

I am not sure that will work. I have a TCU from an 89 and replaced my 91 TCU for a day. Didn't work all that well. Switched it out as soon as I got home. It does work on my 90 though. How it is wired may be the same or nearly so but what about the circuitry? The PN's for the TCU are probably different.

I have a 95 TCM in my 88. I just had to wire the TPS signal to work off the engine side. See notes above.
 
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Actually it can be done and was standard on export XJ's up until at least 95', as can be seen in a few of the pix from gojeeps site. Page down through the article and you can see a POWER/COMFORT switch to the left of the steering column.


US models it's on the right side of the column
 
Aren't' the shifts more firm in "power" mode.. making for less clutch pack wear? I've always run my in power mode.. cause I'm a man :-P *grunt* *grunt*..

The firmness of the shift is controlled by the throttle position (line pressure cable). As ehall stated it's be cause to throttle is open more that the shifting is firmer.
 
I had this on my '89. I very rarely used the comfort setting. Even on comfort the very best that it did was 22mpg on the highway. Both the '96 we had and the '98 that we still have got/get better mileage. This '98 will easily do 26 on the highway at 110 kph with 31" tires. When it was new, with stock tires, it got 28 mpg. Figures are hand calculated in Imperial.
 
I am not sure why anyone would use the comfort mode (I guess Chrysler agreed with me...)

Accidentally put my knee on the power/comfort switch on my friend's MJ while driving it down to NJ to pick up a new transmission for my rig, didn't realize it for a while and was worrying that I might have just fried the transmission in his somehow. I don't like that kind of surprise.
 
I have a power/comfort button on my 95 Limited, and to be honest, I never use it... I leave it in the power mode all the time and it makes no difference to my gas mileage or driveability.

Cheers
Alex
 
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