ZJ 42RE to AW4 swap

[Creepy]

BA's trans has left the building. not rebuilding or replacing with another one. 42re suck.

looking for swap info:

not concerned about driveshafts or spline counts right yet, i can handle all that stuff. got most of it figured out. ba's tcase will be 23 spline, and the donor xj trans will prob be 21 spline, i can swap in a 21 spline input to the tcase.

need to know about electrical!!

spoke with APJ - concerned about needing 2 tps.

anyone know anything?

[justajeep]

I replied to your PM, I have wiring diagrams if you need them. I know the AW4 one almost well enough to not need a diagram now.

[Creepy]

from AlanJ:

I'll check my wiring diagrams. Problem on newer grands is that they run 8v for the sensors, and the AW4 needs 5v from the TPS. I know newer XJ's ran both 5 and 8 for sensors, I assume so they could keep 5v for the AW4.

My Eagle is all 5 volt, so no problem. If the Grand doesn't have 5v on the TPS, you probably would have to run 2 TPS and get a 5v suppy made (Rog C is making me one for the AMX). He might be able to make you one that just drops the 8v max signal from the TPS to 5v max too.

[Creepy]

ok, duh, i'm gonna go look at the tps.....its on the side of the throttle body right? where and how should i measure the voltage? the jeep still runs and drives, barely.

i expect Bill R to contribute to this thread, your trans sucks too! lol

[BawgBoy]

50 cent 7805 voltage regulator will get you 5V from 8V. Simple to wire; 3 pins, 1 = input, 2 = ground, 3 = output. As long as the current draw is low, you don't even need to heat sink it. I have a drawer full if you need one.

[Creepy]

so i could possibly tap the stock tps, not effecting its operation, and filter a lower voltage to the aw4 computer?

[BawgBoy]

So you are looking to change a voltage "range"? Think I understand what you need now, you have a possible 0-8V varying signal you want to change to 0-5V signal. If so, my previous suggestion won't work, I thought you wanted to change a steady 8V supply to steady 5V.
Probably just need a simple zener diode to regulate the max voltage, have lots of those as well.

[Creepy]

i think i need the stock tps performing as stock for the engine controls, and also need a 2nd tps at the lower voltage to run the aw4 computer.

[BawgBoy]

OK, re-read everything and all you need for the voltage issue is a simple 7805 5V regulator. This regulator will take the 8V in and drop it to 5V to supply power to the TPS's ensuring their outputs are 0 - 5V.

[Creepy]

"OK, re-read everything and all you need for the voltage issue is a simple 7805 5V regulator. This regulator will take the 8V in and drop it to 5V to supply power to the TPS's ensuring their outputs are 0 - 5V"

but i need the stock tps at stock voltage, 8V i think.

i'd like to try and run one tps, stock, for engine controls. then also use an output off that at a lower voltage to run the aw4 computer. i want to avoid 2 tps's if i can, seems cleaner to do it that way. might not be possible.

thx for info so far!

[Enos]

Thats exactly what I was thinking Jan, if you can split the output from your stock TPS, run one direct back into the existing wiring for the engine controls and run the other through one of those zener diode things to the AW4, logically it should work if the filtered voltage is at the right level at the right time for the AW4.

[BawgBoy]

I don't think it will shift right though because anytime the TPS output is between 5 and 8V the AW4 will se NO change (5V steady) and think the sensor is at max output when it may not be.

[BawgBoy]

A simple OP Amp circuit will do it Jan, can make you one in 10 minutes. It will output proportionally to the input so the the AW4 only see's 5V when the TPS output 8V.

[bill richards]

chopshop said:

i expect Bill R to contribute to this thread, your trans sucks too! lol

Agreed.... the 46RE sucks just as much as the rest. I've got nothing to add!

Bill

[The Garagemahal]

Alot of info here
www.naxja.org/forum/showthread.php?t=24701&highlight=hold+tranny