32RH transmission torque convertor switch

[Jellis]

2002 TJ x
32hr tranny 3 speed no overdrive. Torque converter staying engaged and causing hard shift and engine to stall at low RPM. No codes are being thrown. I'm told there's a torque converter "switch".



Anyone have any suggestions?

 

[hear]

There is a solenoid on the valve body that engages when the PCM decides it's time to engage. For step 1, I would unplug it from the back corner of the transmission to prove it will unlock (and stay unlocked). The plug is a little different from most, there's a metal clip that you have to pop out and then the thing will easily unplug.

If unplugging it makes you go unlocked, then either the solenoid is stuck closed or something is causing 12V to be on that circuit when there shouldn't be. Replacing the solenoid is not a hard fix, but let's make sure that's what it is first.

 

[BobTJ]

There is a solenoid on the valve body that engages when the PCM decides it's time to engage. For step 1, I would unplug it from the back corner of the transmission to prove it will unlock (and stay unlocked). The plug is a little different from most, there's a metal clip that you have to pop out and then the thing will easily unplug.

If unplugging it makes you go unlocked, then either the solenoid is stuck closed or something is causing 12V to be on that circuit when there shouldn't be. Replacing the solenoid is not a hard fix, but let's make sure that's what it is first.

Just for clarification, I think 12V is normally on one pin of the solenoid connector anytime the ignition is on and the powertrain control module just provides a ground path when it determines that TCC lockup is needed.

 

[hear]

Just for clarification, I think 12V is normally on one pin of the solenoid connector anytime the ignition is on and the powertrain control module just provides a ground path when it determines that TCC lockup is needed.

possibly. I should re-read that section of the FSM for sure.

 

[xXDavidCXx]

There is a solenoid on the valve body that engages when the PCM decides it's time to engage. For step 1, I would unplug it from the back corner of the transmission to prove it will unlock (and stay unlocked). The plug is a little different from most, there's a metal clip that you have to pop out and then the thing will easily unplug.

If unplugging it makes you go unlocked, then either the solenoid is stuck closed or something is causing 12V to be on that circuit when there shouldn't be. Replacing the solenoid is not a hard fix, but let's make sure that's what it is first.

Would you follow the same steps if the TQ converter is engaging and disengaging over and over?

 

[hear]

Would you follow the same steps if the TQ converter is engaging and disengaging over and over?

It wouldn't hurt to try it, but it likely won't tell you much unless you've got a real problem in the TC or valve body.

My initial guess would be that your wiring is bad, but it could easily be a solenoid problem or the PCM. Shorts in the wiring in this area (over top of the transmission) are not at all uncommon.

I've never tried it, but you can isolate the solenoid as the problem by hooking up a test light to the pigtail side of the TCC connection, and then test driving to see if the light matches up with how the lockup seems to behave for you. Having the test light AND the TCC both in the circuit requires some clever parallel wiring, plus the fact that it's under the jeep makes it complicated.... if I ever have to do this I think I would run the test wires up through the e-brake or transfer case hole in the tub.

If the light stays lit but the TCC acts up it means the solenoid is bad. If the test light misbehaves, then it's either wiring or PCM.

 

[xXDavidCXx]

It wouldn't hurt to try it, but it likely won't tell you much unless you've got a real problem in the TC or valve body.

My initial guess would be that your wiring is bad, but it could easily be a solenoid problem or the PCM. Shorts in the wiring in this area (over top of the transmission) are not at all uncommon.

I've never tried it, but you can isolate the solenoid as the problem by hooking up a test light to the pigtail side of the TCC connection, and then test driving to see if the light matches up with how the lockup seems to behave for you. Having the test light AND the TCC both in the circuit requires some clever parallel wiring, plus the fact that it's under the jeep makes it complicated.... if I ever have to do this I think I would run the test wires up through the e-brake or transfer case hole in the tub.

If the light stays lit but the TCC acts up it means the solenoid is bad. If the test light misbehaves, then it's either wiring or PCM.

Just to add some additional details, I’ve burnt through a few TQ converter solenoid fuses under the dash, and I occasionally get a CEL when it misbehaves, but not always.

I think the fuse issues points to maybe an issue in the loom, also consider I have a 1 inch BL and tummy tuck, so the trans is shoved up as far as it can go.

 

[hear]

Just to add some additional details, I’ve burnt through a few TQ converter solenoid fuses under the dash, and I occasionally get a CEL when it misbehaves, but not always.

I think the fuse issues points to maybe an issue in the loom, also consider I have a 1 inch BL and tummy tuck, so the trans is shoved up as far as it can go.

if you're blowing that fuse, I would STRONGLY suspect wiring. Unplug the loom from the trans & t-case, and also at the rear driver's corner. Then pull it all up into the engine bay. Fix it, re-loom & re-tape...you'll feel like a new man.

 

[xXDavidCXx]

if you're blowing that fuse, I would STRONGLY suspect wiring. Unplug the loom from the trans & t-case, and also at the rear driver's corner. Then pull it all up into the engine bay. Fix it, re-loom & re-tape...you'll feel like a new man.

Thanks, this will take less time than replacing the solenoid.

 

[hear]

Thanks, this will take less time than replacing the solenoid.

Debatable.

 

[mrblaine]

Debatable.

Very

 

[xXDavidCXx]

Debatable.

I guess what I meant is I don't have to tear into the trans. But sure, finding the issue may take time.

 

[hear]

I guess what I meant is I don't have to tear into the trans. But sure, finding the issue may take time.

We both knew what you meant.

If you have a drain plug on your trans pan, then maybe the difficulty/hassle factor changes a little. Regardless, time spent inspecting & re-looming your harness will be rewarded long term. Even if future xXDavidCXx is never fully aware of how much past xXDavidCXx helped (future) present xXDavidCXx.

#tenet

 

[xXDavidCXx]

We both knew what you meant.

If you have a drain plug on your trans pan, then maybe the difficulty/hassle factor changes a little. Regardless, time spent inspecting & re-looming your harness will be rewarded long term. Even if future xXDavidCXx is never fully aware of how much past xXDavidCXx helped (future) present xXDavidCXx.

#tenet

Found time to pull the engine and transmission harness out.

Overall condition of the wire loom is poor. Everything is brittle, most of the connectors don't snap on or stay on anymore.

Checked ohms between C2 PCM B11 and the orange/light green wire on the TCS connector and got.... 0.00

I didn't see any visible damage to the wires between the PCM and the TCS connector.

So, replace the solenoid next?

 

[hear]

I would be removing all that tape and checking underneath it as well.

Checking for 0 ohm between the ends of a wire is a good check, but it doesn't tell you if there is a short to another wire somewhere in there. Also one strand of wire is enough to show continuity, but a test light can probably do a better job showing you just how good the wires actually are. Anyway go over it with a fine toothed comb, and fix anything that is problematic. I find that the insulation tends to shrink back near the connectors, so that's worth looking at as well. Then re-tape, re-loom, and re-place the harness & test drive.

If you don't find anything wrong with the harness (a) it will be a first, and (b) I would probably tackle the solenoid next.

 

[xXDavidCXx]

I would be removing all that tape and checking underneath it as well.

Checking for 0 ohm between the ends of a wire is a good check, but it doesn't tell you if there is a short to another wire somewhere in there. Also one strand of wire is enough to show continuity, but a test light can probably do a better job showing you just how good the wires actually are. Anyway go over it with a fine toothed comb, and fix anything that is problematic. I find that the insulation tends to shrink back near the connectors, so that's worth looking at as well. Then re-tape, re-loom, and re-place the harness & test drive.

If you don't find anything wrong with the harness (a) it will be a first, and (b) I would probably tackle the solenoid next.

Used my test light on both wires, and they both light up good.

I did unravel more tape and found one unrelated wire with the core exposed, but nothing else that looks out of the ordinary.

I may get a new to me harness just to have better connectors, but it looks like the solenoid is next.

 

[xXDavidCXx]

Found the issue

Both TCS wires exposed

 

[xXDavidCXx]

A better shot

 

[hear]

There ya go.

https://www.rockauto.com/en/moreinf...hjeeGonuNeRPruMGLMI+/lUXcbdVBr95inunCsz3P4Q==

 

[xXDavidCXx]

Replacement is already installed.

Waiting on a few replacement connectors for the wire harness rebuild project.