Hi all, I have been lurking through all the AW4 reverse question threads with great wonderment and a bit of confusion. Now that I am an official member... I too have a 1990 I-6 with AW4, both of which have been recently rebuilt. This is a Jeep that I am assembling from a multitude of directions, engine from one vehicle, trans from another, harness from a third, so I do not have historical data on all components, namely the TCU. I have verified the NSS is making all the correct connections and I have completed most if not all of Cruiser's recommendations on grounding. I have not yet taken care of the two splices in the wiring loom, but will do so shortly.
With the TCU connected (either one, I have two at the moment) I have forward gears, but when I initially shift to reverse (Wheels off the ground) the tires begin to nudge in the correct direction but then nothing. Typical as all others, it's as if it is in neutral.
With the TCU disconnected reverse seems to work correctly. I have not yet done a driving test as I was hoping to do so with the transmission working automatically. I will probably just do the manual shift driving test so I can continue to break in the engine properly. Then go back to the TCU issues.
So - my question is: What is the TCU doing or not doing that messes with the trans ability to shift into reverse properly? the NSS for reverse, only seems to have an effect on the backup lights. but it must be doing something else to cause it to not function in reverse when it is connected... All the threads I've seen that reference this problem seem to Peter out into other members asking, "so did you get this fixed?", which then is met with radio silence from the OP.
Does the TCU only operate the three solenoids? Tonight or tomorrow first thing I will chick the signal from the TCU to the wires going to the solenoids. I did'nt have the correct pinouts this morning - The signal to the TCU is correct for all NSS positions. Its a head scratcher if you ask me... Any thoughts? have I missed a thread? BTW - you guys are awesome - I had a rough idle issue that was a simple mistake on my part but your thoughts set me straight!! Maybe this is likewise.
Cheers,
Mark
With the TCU connected (either one, I have two at the moment) I have forward gears, but when I initially shift to reverse (Wheels off the ground) the tires begin to nudge in the correct direction but then nothing. Typical as all others, it's as if it is in neutral.
With the TCU disconnected reverse seems to work correctly. I have not yet done a driving test as I was hoping to do so with the transmission working automatically. I will probably just do the manual shift driving test so I can continue to break in the engine properly. Then go back to the TCU issues.
So - my question is: What is the TCU doing or not doing that messes with the trans ability to shift into reverse properly? the NSS for reverse, only seems to have an effect on the backup lights. but it must be doing something else to cause it to not function in reverse when it is connected... All the threads I've seen that reference this problem seem to Peter out into other members asking, "so did you get this fixed?", which then is met with radio silence from the OP.
Does the TCU only operate the three solenoids? Tonight or tomorrow first thing I will chick the signal from the TCU to the wires going to the solenoids. I did'nt have the correct pinouts this morning - The signal to the TCU is correct for all NSS positions. Its a head scratcher if you ask me... Any thoughts? have I missed a thread? BTW - you guys are awesome - I had a rough idle issue that was a simple mistake on my part but your thoughts set me straight!! Maybe this is likewise.
Cheers,
Mark