ParadiseMJ Posted November 22, 2013 Share Posted November 22, 2013 Other than the obvious differences in the color of the connecters (one is light gray 87-89, the other is green 91-?) for the different TCU's can anyone tell me what the difference is in the two TCU's. Are the pins in different order?? http://www.ebay.com/itm/53008383-Jeep-Cherokee-6cyl-Transmission-Computer-Control-Module-TCM-TCU-1991-91-/160951300715?pt=Motors_Car_Truck_Parts_Accessories&fits=Make%3AJeep&hash=item257971f26b&vxp=mtr http://www.ebay.com/itm/1987-1989-JEEP-CHEROKEE-TRANSMISSION-CONTROL-COMPUTER-MODULE-TCM-8953005305-/290985047053?pt=Motors_Car_Truck_Parts_Accessories&fits=Make%3AJeep&hash=item43c00f740d&vxp=mtr If my Renix truck has an HO transmission...does it use a Renix TCU with a Renix wire harness OR does the HO tranny use an HO TCU with an HO harness. Or does it matter?? Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 22, 2013 Share Posted November 22, 2013 The green connector is the same TCU I have in my 91. The 91 and 92 TCUs also have a different p/n's. What that difference is :dunno: . I can send you the pinout of the 91 TCU and if you have the Renix TCU diagram you can compare to make sure the correct function is on the correct pin? The 32-pin TCU's have many unused pins. EDIT: Attached the pic. You might have to blow it up a bit. Link to comment Share on other sites More sharing options...
ParadiseMJ Posted November 22, 2013 Author Share Posted November 22, 2013 Thank you Don. Just looking at this I can tell it's different from the Renix. Which would explain why I'm not getting some readings right. Link to comment Share on other sites More sharing options...
ParadiseMJ Posted November 22, 2013 Author Share Posted November 22, 2013 FIXED!!! THE BEAST IS *&^#$%^@ FIXED :banana: :banana: :banana: :banana: :banana: :banana: :banana: :banana: :banana: :banana: :banana: After my AW4 swap, I have been chasing my tail with this wire that wire, that harness, this harness, every possible configuration.wondering why I couldn't get a signal on my TPS, not shifting properly, no lock-up...no kickdown...no second gear, NO POWER!!! After I looked at the pin outs for the HO TCU and the Renix TCU it all became crystal clear to me. Even though the tranny is an HO era tranny, the harness, TPS, TV etc. etc. is all Renix. Today I went to the junkyard, got the Renix TCU out of the same Renix Jeep (XJ) that I got the harness from. Came home and in 10 minutes I had the "new" TCU in...and after taking a quick drive around town, ALL of the problems I had are GONE and the Jeep runs like it should. Time for Thanksgiving . Link to comment Share on other sites More sharing options...
Oyaji Posted November 22, 2013 Share Posted November 22, 2013 Awwwww hell yeah! Congratulations! Now need to see if it is done with the overheating problem... ;) Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 23, 2013 Share Posted November 23, 2013 Good thing the TCUs retained the same 32-pin connector throughout the years. Now I know why the 1992 TCU didn't work right in my 91. The converter lockup signal appeared on a different pin. You probably were not getting the speed sensor feed either. Do you have a Renix TCU pinout diagram you can post up to compare the two? Link to comment Share on other sites More sharing options...
ParadiseMJ Posted November 23, 2013 Author Share Posted November 23, 2013 On the 91 TCU I had in there...the TPS was not showing up, as there seemed to be only one TPS wire originating at the TCU. The 88 TCU I snagged today shows 3 pins...TPS input, TPS output TPS ground...as the 88 TPS is adjustable and the HO TPS is NOT. The first thing I checked with the new TCU in was the TPS signal. Where there once was none, there was a nice strong signal (VDC) at the square connector with the key ON, like it's supposed to have. Oyaji I took it for a 40 mile round trip (up that problematic hill) and never went over 195. Link to comment Share on other sites More sharing options...
Oyaji Posted November 23, 2013 Share Posted November 23, 2013 40 miles! Good deal - sounds like you got it whupped then. . I'm curious - was that trip before or after your transmission fix? I'm wondering if the transmission problem was part of the overheating problem? Link to comment Share on other sites More sharing options...
ParadiseMJ Posted November 23, 2013 Author Share Posted November 23, 2013 40 miles! Good deal - sounds like you got it whupped then. . I'm curious - was that trip before or after your transmission fix? I'm wondering if the transmission problem was part of the overheating problem? It was AFTER I swapped the TCU. The tranny trouble was definitely about the tranny (just as you had suggested) because the truck was having so much difficulty getting around, especially up "horror hill". I took it up that hill yesterday and another shallower but longer grade and not even a hint of getting hot. Woohoo!! The TPS wiring from the TCU on the Renix than they are different on the HO TCU. When hornbrod sent me the TCU print-out the light went on for me. Duh!! Anyhoo, Thanks to all who chimed in and helped me on this over the last months. I have my truck back and it's purring like a kitten. Link to comment Share on other sites More sharing options...
knever3 Posted November 23, 2013 Share Posted November 23, 2013 I may have this problem myself!! The donor I bought had the both the TPS sensor plugs cut off and new ones soldered on. The transmission plug was cut off and replaced too. I may have the wrong TCU for my trans. It won't go into OD or the torque converter will not lock up and the thing idles sky high. No power is right, it seems like the trans is taking all the power from the engine. The new stroker I am NOT impressed with could very well be a trans problem. I will do some research myself, one question. How do you tell what year your trans is and what TCU to use for it? I have a spare trans and transfer case in my shed I could reference also. Thanks!! Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 23, 2013 Share Posted November 23, 2013 There is an ID plate on the right rear side that has the AW4 model number and serial number. Get that then call a transmission shop to ID your tranny (if you can't find anything on-line). Then you can cross the year in the Mopar parts manual to ID the correct TCU for it. Do you have the AW4 manual(s)? Link to comment Share on other sites More sharing options...
knever3 Posted November 23, 2013 Share Posted November 23, 2013 There is an ID plate on the right rear side that has the AW4 model number and serial number. Get that then call a transmission shop to ID your tranny (if you can't find anything on-line). Then you can cross the year in the Mopar parts manual to ID the correct TCU for it. Do you have the AW4 manual(s)? No I don't Don, I would love to buy the FSM's for the trans and electrical and mechanical stuff. I just haven't found them yet. Thanks for the info! Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 23, 2013 Share Posted November 23, 2013 Shoot me a PM with your email addy and I can send yo the AW4 stuff I have. :thumbsup: Link to comment Share on other sites More sharing options...
knever3 Posted November 23, 2013 Share Posted November 23, 2013 done Link to comment Share on other sites More sharing options...
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