Torque Converter lock up switch-TCC

Does anyone know how to change out the TCC in a 94 grand am? We were going to pay someone to do it but it is going to run us approx. $350 I have put too much money into this car already my husband has done all of the work but we can't find anything that tells us how this is done. I have tried to find the Haynes automatic transmission overhaul manual but I can't find it anywhere! Please help if you know how to do it could you please tell me the entire process? Or if you know where I can find it online or something that would be great too!! I need to know asap if possible my husband wants to do this tomorrow because I can't even drive through town! our town is like 5 miles. It is crazy. it has only been doing this for 4 days but it wont stop now! Please help Thanks Alicia

Welcome to the forum!! The problem with the TCC is the fact that it is not a DIY job to replace. It is inside the transmission and requires a lot of expertise to replace. I would have the tranny shop change it for you. It is well worth the $350 to have someone else do it for you.

well I guess mine is unusal I don't know my husband talked to a guy at the tranny shop here and he said he has been working on transmissions since 1975 and hasn't EVER had to do one on the car like mine. it is a 3.1 v6 4 speed is that unusal? do you know hwre eI can find the steps on how to do this? just to have an idea? thanks

Best place to find out how to do it is in the factory service manual, alldatadiy.com will sell you a year of factory shop manual access for $25...If you wonder how good they (alldata) are they are used by many many shops including dealerships. You can do that or you could buy the factory service manual for your car from somewhere.

A good source for a manual like that is ebay, most people get rid of their manuals when they sell a car.

Well I am having the same problem with my 01...6 cyliynder...took it to a friend of mine and he said...drop the pan not the whole transmission and make sure the smalll vent that is in there is not plugged by tranny gunk...and the part at auto zone was 24 dollars....you identify the part when the pan is down.....change it and rplace trans fliud and seal of course.....I am just about to start mine...I can let you know how it goes......Tomm











Does anyone know how to change out the TCC in a 94 grand am? We were going to pay someone to do it but it is going to run us approx. $350 I have put too much money into this car already my husband has done all of the work but we can't find anything that tells us how this is done. I have tried to find the Haynes automatic transmission overhaul manual but I can't find it anywhere! Please help if you know how to do it could you please tell me the entire process? Or if you know where I can find it online or something that would be great too!! I need to know asap if possible my husband wants to do this tomorrow because I can't even drive through town! our town is like 5 miles. It is crazy. it has only been doing this for 4 days but it wont stop now! Please help Thanks Alicia

well I checked with every auto place around here none of them have the one for my car they said they haven't ever had to changed it on a 4 speed. so now what? my husband unplugged something which we thought was the soloenoid. we read that this could be done. but when we did it we had no passing gear of anythign it took forver to get to 30mph! so was that it? we unplugged it and ran it for about 30 min drove it and everything did die. then we plugged it back in because my husband was leary about having it off because of what it was doing after we plugged it back in it has been fine. it hasn't died or anything, so would that have been the soloenoid? or possibly something else. Thanks for all the info everyone.

I thought mine was the same a little while ago... I have the same car...1994 3100 4spd auto...is your tranny plug on the front of the tranny under the throttle body?

If so, pull the plug, take a jeweler's screwdriver small enough to get into the plug, and push the tan wire out through the back of the plug towards the wires...you will have to carefully spread the wires and unclip the little red retainer thingy...I did that to mine and it seemed to work...according to the wiring diagram in the Haynes manual, the tan wire feeds the TCC.

If that doesn't do it, try the pink wire as well...they are both associated with the TCC and it is possible to backfeed the solenoid through the pink wire (at least I would think it is)

Somebody please chime in if I am reading the diagram wrong, but it helped mine with no ill effects (even though it turned out it wasn't the TCC on mine...it still shifted and had all gears EXCEPT the final lock out shift into overdrive...

Give that a try and see if it helps...I would not recommend driving a long time like that if in fact it does help...it would be a VERY TEMPORARY band-aid until you could find a shop that could change out the TCC...worst case scenario, there is always a dealership.

so what exactly was your and how did you know for sure? we unplugged it and it will run now but it doesn't have any speed until about 30mph and doesn't really shift all that much seems like you are taking off in 3rd gear all the time. really weird. but I unplugged it because I got to the end of my driveway and it died I couldn't get it to start so I unplugged it and it started and got me to work. so it will work for now. do you know how to change it or where I could get one for our 4 speed no one seemd to have them around here. Thanks again!!!!!!!!!!

so what exactly was your and how did you know for sure? we unplugged it and it will run now but it doesn't have any speed until about 30mph and doesn't really shift all that much seems like you are taking off in 3rd gear all the time. really weird. but I unplugged it because I got to the end of my driveway and it died I couldn't get it to start so I unplugged it and it started and got me to work. so it will work for now. do you know how to change it or where I could get one for our 4 speed no one seemd to have them around here. Thanks again!!!!!!!!!!
What he's saying is that you can unplug JUST the TCC... not the whole trans (which needs to be plugged in inorder to properly function, as the Trans is electronically controlled). Basically, the TCC has a wire that is 12V+ all the time, until you hit the brake, where the brake switch will cut the power to the TCC effectivley turning it off unlocking the converter.

If you're unsure of which wire, all you need is two people and a test light. Just go around the plug until you find a wire that is 12V+ and then see if it goes dead when you hit the brake... if it does, then cut that wire (but plug in the rest to the trans). I had to that with my 92 Transport, and it worked fine.. recently, one person has said that it will fry the trans, but after 40K miles on the transport... it has yet to show any signes of burning up.

If you wan't it to last, get it fixed properly.... You're taking chances by using anyother way.

now up to this point we thought it was the TCC but this mourning I started it up andthen went to back up got about 15 seconds down the driveway and it died couldn't get it to start unhooked the what we believe is the TCC and it started up. would this still be the TCC ?

alright well I went and had the diagnostics done on it and they told me the readings were....... this if you can help explain this it would be greatly appreciated also if you know what it means and how to fix it would be great too. Thanks this it what they wrote on a peice of paper.

TFT transmission fluid temp. sensor
(wiring, open circuit, TFT sensor, ECM)

exhaust gas recirculation solenoid
(wiring, EGR valve, ECM)

Please help..... Thanks

Ummm... Did you disconnect the battery for 15min. after hooking up the trans again?? If not, they could be reading all the stored codes from you trying to drive with the harness unplugged.

Just curious:2cents:

yes we did. please help. do you have any idea what that would mean? TFT sensor and EGR solenoid? or where they would be located?