Hi everybody. I have a serious problem and am in great need of your help.

I have a 2003 Monte Carlo LS, 3800 V6 with a 4T65-E Electronically controlled transmission.

OBD2 Code: P0742-Torque Converter clutch stuck on.

Symptoms; Car drives and shifts fine when cold, but once it warms up to operating temp, theres a rough "Jerk" when it switches gears (All Gears)
In the research I did, I found that the "4T65-E" transmission is all electronically controlled, and there are other things that would cause this problem besides a faulty TCC Solenoid.
Does anyone know of any issues that would cause the Electronic TCC solenoid to be stuck On??
I know that the ECM sends signals to the solenoid telling it when to engage and disengage, but in this case, it does not disengage.
ANY ADVISE WILL BE VERY HELPFUL!

Already tried:
-Trans filter and fluid change (No flush)
-o2 sensor sensor 1 bank 1 replaced.
*No change*

 

Well it could be a number of things, primarily though you're correct. TCC solenoid, or torque converter failing... But the jerking at every shift indicates a possible Pressure Control solenoid failure, or even the 1-2 and 2-3 shift solenoids crapping out...

You could change the brake switch (under your brake pedal), it has something to do with the torque converter locking up sometimes. Other than that, you're gonna have to drop the cradle or pull the engine to change solenoids. Good luck.

 

I dont think that it's the 1-2,2-3 solenoids because it also Jerks when it shifts to OD. I think I am going to check that brake switch thing you suggested. I would much rather go through all other possibilities before sending it to get rebuilt. Thanks!!

 

No problem, but if you only need solenoids it doesn't require a rebuild... Just takes a lot of work to get the side cover off the tranny (this is why the engine/trans has to be pulled, or have the cradle dropped, clearance issues). Once the side cover is off, I replaced all 4 solenoids in 5 minutes lol

 

Yah thats the thing, its easy to do the work but getting to it is the pain in the ***. Any idea where I can find a complete wire diagram for that tranny?

 

It's literally what's happened to mine and many other Montes on the forum. It's rather ambiguous and stressful, really. But it does come down to the shift solenoid. Cheap part. Hefty $$$ to drop the tranny/lift the engine out to get to it.

Edit: My problem isn't the torque converter (although I believe both problems come down to the solenoid.)

 

The 4T60 transmission family is definately not easy to work on. I remember that years ago it was as simple as dropping the tranny pan, pull out the filter, and the solenoids were right there.
Im an old school mechanic but ive been out of the game for 10 years, so I am good at basic mechanical but todays cars are way to complex.
I guess the question now is to fix or sell.