Looking for info from 1990 Cherokee FSM

I'm finishing up an aw4 swap into a 2.5L YJ and for the most part it is working. I've been using the wiring diagrams from a 94 FSM I have which for the most part has worked. What I am looking for is the page in the FSM which shows the TCU electrical hookup diagram, and the page which shows the TPS. Specifically the 90 cherokee that had a 2.5L and AW4.

ANyone got it?

Thanks

I think I've got the wiring diagrams from 1990 scanned and upped at RENIXPower - groups.yahoo.com/group/RENIXPower.

If you don't see it there, or it doesn't help you, let me know. I don't have a scanner, but I do have a 1990 FSM, so we can work something out...

Perfect, that is exactly what I needed.

It appears that I need to somehow invert the voltage from the TPS to the TCU. The 90 version of the TPS provides a 0-5V signal for the ECU and a 5-0v signal for the tcu. The 94 version of the TPS provides only a 0-5.

Thanks for the info.

If the ECU output runs the same direction as the TCU you're using, why not just use that and leave off the other wiring? If it's a variable voltage, a micro-amp signal will work - and splitting the TPS output (voltage divider) will be rather more than a few microamps (probably a few dozen milliamps - I haven't checked.)

That should give you a usable signal, without the need to invert your voltage.

5-90 said:

If the ECU output runs the same direction as the TCU you're using, why not just use that and leave off the other wiring? If it's a variable voltage, a micro-amp signal will work - and splitting the TPS output (voltage divider) will be rather more than a few microamps (probably a few dozen milliamps - I haven't checked.)

That should give you a usable signal, without the need to invert your voltage.

Click to expand...

What ECU output?

What years are we talking about? The Renix setup had a dual output TPS and the output to the TCU ran backwards from the output for the ECU. The Chrysler engine computers starting with the HO engine had a single output TPS that went to the ECU and then the ECU had an output that went to the TCU (that ran backwards as well, I think).

Depending on what year XJ we are talking about, you either need to get the correct dual-output TPS if its a Renix, or if a later model tie into the outputs from the ECU. If it was originally a manual, the ECU may not have the outputs and you'll need to swap it as well.

Or build something to convert the signal from the existing TPS as someone else suggested. Not too hard to make an inverter using an op-amp, but you'll need some electronics skills.

1990 TCU for a 2.5L on a 94 2.5L YJ that used to have an ax5

Think I came up with a solution. I cut up an extra throttle body and created a bracket that will let me attach it to one of the throttle body bolts. Still need to create a solid linkage between the 2 arms - using the peg normally used for the AC idle booster.

Worked good, the linkage is temporary - didn't have 2 of the clip ends laying around so I just used part of an old throttle cable to see if it worked. Tranny shifts like it should now.
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