Transmission Not Shifting

93 4.0 AW4

This is actually our 1700 Jeepspeed car.

Currently has a Bretts AWShifter installed. At the Baja 1000 we had some issues with the joystick we were using to shift the transmission sticking and jumping too many gears and so on.

So we rebuilt the joystick and it works great now. The LED's on the AWShifter show that it works great.

But for some reason the transmission will not shift at all now. If I start the Jeep with the AW turned on, it is in 4th gear when you put it in Drive as it should be and won't take off from a stop hardly at all.If I bump it down to 1st it downshifts fine and I can take off. But I cannot upshift.

If I turn the AW Shifter off (for those of you not familiar, when it is off it bypasses and the trans tcm takes over just like factory) the car takes off in first but will not shift out of first.

TCM fuse is good, tried a replacement TCM entirely. I even tried hooking our new RA Designs shifter up (wired it down right by the solenoid wiring at the tranny) and couldn't get it to shift the gears either.


The only other thing we've done is drop the pan, change the filter, and change the fluid.

Any ideas?

Sounds like a bad solenoid in the transmission. My 97 did exactly the same thing one morning when I put it in drive it started in 4 (OD) gear and I basically had to manual shift it starting in 1-2 then kicking it up to 3 and then D at the right points. I did this the whole day until I could take it to a transmission shop. They told me what was wrong but didn't tell me what solenoid it was so I can't help you there.

Mine doesn't do that. It stays in 1st no matter how you shift it (when all the aftermarket shifters are disabled). It doesn't matter where you put the selector.

Had this happen on a renix, would not shift out of first. Throttle position sensor fixed it.

Interesting. I would've figured that the TPS would be ignored when I use my RA shifter...

That's the second person to suggest that, I'll give it a shot.

PS - Your post count is 6,666 right now.

The two plugs up near the trans dipstick tube carry all the signals to and from the AW4, TPS, VSS, Solenoids etc. IIRC, one connector is gray and the other white. Unplug them and inspect for corrosion and pins bent or backed out. Spray them out with electrical cleaner, add dielectric grease,and plug them back in.

Not the TPS, tried a new one, no difference.

Checked the two plugs you've just mentioned, they seem clean and contacted well.

The RA designs shifter is wired into the harness about 6" from where it travels into the transmission. And that won't shift the trans. This makes me think its wires from that point to the solenoids, or the solenoids themselves.

If not the connectors by the trans dipstick then its a solenoid. All 3 can be had for less than 200 bucks online.
Ron

Tested the solenoids when we had it apart to swap out the wiring harness that runs to them, they are functioning fine.

Disconnect all electric to the trans and it should be able to go through the gear manualy. this will prove its electric and not a mechanical problem. Just because a light lights up does not mean the power is getting to the solenoid. this should be your next test.

We did not test them with a light, we tested by putting power to them.

They do function. But as you said, with no electronics, we still get nada.

Is at a Trans shop now.


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