Hummer H3 P0741 TCC Solenoid Circuit Performance/Stuck Off

[Kyle]

Okay I've found very little info regarding this issue, so I will be adding to our knowledge "library" we have here on the forum.

So to start, I was driving down the freeway,75ish, when i noticed i could play with the rpm vary easily, i could vary from 2500rpm to 3000rpm with just a light touch on the throttle, which told me the torque converter wasnt locking up, i thought nothing of it, got to my destination and parked the car and googled around but nothing really jumped out at me. So on my way home, back at 75ish on the freeway the converter was locking up and acting normal, was on the phone with chris and he and both agreed it was fluid related probably or a solenoid. soon as a hung up the phone, Bam, CEL pops on, I loose lock up and i go oh great. So i get home read the DTC and its (P0741 TCC Solenoid Circuit Performance/Stuck Off) did some research on some trans forums and other GM forums and concluded it must be one of the two TCC solenoids. One easier to change than the other. So lets begin, waiting on the parts to arrive around noon! will update with pics along the way!

 

[CaseyS]

You can. Change both of those with a pan drop. I would start with the off/on solenoid. That is part of the main harness and I think the replacement you have to solder in.

 

[Kyle]

You can. Change both of those with a pan drop. I would start with the off/on solenoid. That is part of the main harness and I think the replacement you have to solder in.

According to this image, the off/on one is the one held in by the two bolts with the copper windings to the left of the blue connector and the one I'm changing out is the easiest one which this dude is changing out right now, if the shop didnt have a week wait for the off/on one id be doing both at the same time. unfortunately im taking a gamble.

 

[CaseyS]

My money is on the off/on one. Is there not a transmission supply shop anywhere around you? That should be a shelf item just about anywhere.

 

[Kyle]

My money is on the off/on one. Is there not a transmission supply shop anywhere around you? That should be a shelf item just about anywhere.

this is the one they gave me, I believe it's the off/on solenoid actually and not the other solenoid I thought it was. I also took the car for a drive and the check engine light is gone and the trans locks up perfectly, guess it fixed itself [emoji23] I still plan to swap out this part for good measure!



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[lowtrac]

It's good that you can access that fairly easily. I had a 2002 Cadillac Seville with a bad TCC solenoid. You have to drop the engine cradle because there's not enough clearance to get the side cover off the transaxle while it's inside the frame rails. The dealer wanted $1500 to replace a $20 part. Me and a friend of mine did it in his garage. It wasn't what I'd call fun.

 

[Kyle]

Well I think I found the real issue, went to unbolt the pan, all the bolts were loose. Like scary loose. Think it may have been dripping fluid, So drained the pan nothing out of the ordinary, didn't change the solenoid since it involved cutting and using crimp connectors. Wasn't something I felt comfortable doing myself. But I did tackle the external trans cooler install. Here's some pics.

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[Kyle]

Update, solenoid was changed out today and the TCC is locking up and functioning normally! Hopefully it was the fix!


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[Kyle]

Update again, that wasn't the fix, lights back on and no lock up, I will now try the second solenoid, and if that doesn't do it, the valve body is possibly at fault or the torque converter itself needs to be changed


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[Reloader]

Last one I tried to deal with on this issue turned out to be a smoked torque converter I think. Fluid was very dirty which turned out to be clutch material from inside torque converter. We tried cheapest fix first being solinoids and harness assembly then other solinoid not with harness and changing trans fluid several times to get it clean. I was willing to try installing reman converter but with all that debris getting pumped through system couldn't guarantee it would stay trouble free. Reman would have been best for this one. I just put GM reman trans in my Alpha as I had this loud ticking from my torque converter. Something coming apart internally. Sat on hoist for 5 weeks till I decided to just go with GM reman. You can't beat the warranty on it. I looked into a performance rebuilt unit but all had piss poor warranties and a lof more $$$. I got GM reman for $1900. Also went through TC at same time and rear main seal since it was out of vehicle. Did find loose snubber bolts in both my TCs. I built my spare non adventure case into a 4 to 1 at same time since I had a 4 to 1 reduction assembly laying around.

 

[Kyle]

Last one I tried to deal with on this issue turned out to be a smoked torque converter I think. Fluid was very dirty which turned out to be clutch material from inside torque converter. We tried cheapest fix first being solinoids and harness assembly then other solinoid not with harness and changing trans fluid several times to get it clean. I was willing to try installing reman converter but with all that debris getting pumped through system couldn't guarantee it would stay trouble free. Reman would have been best for this one. I just put GM reman trans in my Alpha as I had this loud ticking from my torque converter. Something coming apart internally. Sat on hoist for 5 weeks till I decided to just go with GM reman. You can't beat the warranty on it. I looked into a performance rebuilt unit but all had piss poor warranties and a lof more $$$. I got GM reman for $1900. Also went through TC at same time and rear main seal since it was out of vehicle. Did find loose snubber bolts in both my TCs. I built my spare non adventure case into a 4 to 1 at same time since I had a 4 to 1 reduction assembly laying around.

Good to know, I'm going to just have the whole trans overhauled this month and have all stage 2 parts installed just so I know it's dependable and going to last me


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[Kyle]

I wanted to kind of give an update on this as I've been reading a lot of info on torque converters,transmissions etc. The fix is changing out the torque converter, and upgrading the valve body because of the check ball failure that's common with 4l60e transmissions. If you have a high mileage transmission it is advise to just overhaul the transmission.