Code 0743 trans help!

r/tguy02 · Post by **r/tguy02** » Wed Jan 27, 2010 9:15 am

Well the problem is with my 01 neon 3spd atx. (bonestock)
about a week ago the fiancée takes it in to have the trans flushed, filter replaced, and the pan gasket replaced. Everything seemed fine. Then just last night we were sitting in the parking lot with the car running and the cel pops on. Thought that was odd and figured I'd check it when I got home. We leave and as soon she got it up to speed and went to slow down it started shuddering and acted like it didn't want to downshift. Untill she came to a complete stop then it would force itself into 1st. It would repeat the same thing every time She went to slow down. So anyways I pull the code at this point, got 0743:
"torque converter clutch solenoid/trans relay circuits an open or shorted condition detected in the torque converter clutch (part throttle unlock) solenoid control circuit. Shift solenoid C electrical fault-aisin transmission."
so first thing I did was check the fluid, it's barely on the end of the dipstick! So I add a qt and 1/2 to bring it back up to normal. Pulled the batt to clear the code and started it back up. Cel comes right back on but I took it for a drive anyway. It goes up through all the gears normal but anytime you slow down or come to a stop it doesn't want to downshift from 3rd. So I manually downshifted when I needed to stop and that worked. I also noticed if I leave it in 2 the trans behaved normally. It's only 3rd gear that seems to have the issue. Reverse also works fine.
Srry for the long description...please help!

Post by **occasional demons** » Wed Jan 27, 2010 9:46 am

TC solenoid is bad, or w/e switches it is sticking. It sounds like it is not releasing the lock up clutch. Thus wanting to keep going. It would be similar to hitting the brakes on an MTX car while not pushing in the clutch. If that's what it seems like, then I would bet on the solenoid, or something in the control circuit.

Edit: Don't worry about the "Shift solenoid C electrical fault-aisin transmission" part. That would only apply to AisinWarner ATX equipped vehicles, like the Jeeps.

r/tguy02 · Post by **r/tguy02** » Wed Jan 27, 2010 11:07 am

Thanks for the info and yes it feels just like hitting the brakes without pushing in the clutch on an mtx. Any idea on what it costs to replace said solenoid? You think the guys that did the fluid change couldve caused it? if so I'm taking it back there and demanding they fix it free.
*how hard is it to replace the solenoid?

Danteneon · Post by **Danteneon** » Wed Jan 27, 2010 11:26 am

The solenoid itself is part #4799954AA...MSRP $15.10 Labor may be an hour or two since it sits above the valve body.

r/tguy02 · Post by **r/tguy02** » Wed Jan 27, 2010 11:39 am

THanks Dante for the part #

Danteneon · Post by **Danteneon** » Wed Jan 27, 2010 11:53 am

No prob. Let us know what the shop says.

Post by **occasional demons** » Wed Jan 27, 2010 12:24 pm

I doubt the fluid change did it. The wrong fluid may make it shudder when it engages, or modulates to create partial engagement, but I don't think it would cause the solenoid to fail.
Basically the pan needs dropped, and the valve body removed to change it. At least I think the VB needs to come out.
There should be an electrical connector near where the shift linkage rod enters the case. You could unplug that, and it should keep the TC from locking up. It might not be a bad idea, just to keep any unneeded stress off the lock up clutch. The CEL will still be there, because you would now have a confirmed open circuit.

r/tguy02 · Post by **r/tguy02** » Wed Jan 27, 2010 12:30 pm

Ok I'll do that for the time being. I might just bite the bullet and fix it myself this time, I just hate working on cars in this weather

I'll post up when I find out more details

r/tguy02 · Post by **r/tguy02** » Wed Jan 27, 2010 9:37 pm

Looks like I'm def going to tear into this trans tomorrow to replace the solenoid, anyone have some diagrams showing how to get to it? My hayes manual is all I've got for the 01 and it sucks...

Post by **occasional demons** » Wed Jan 27, 2010 11:57 pm

2) Install TCC solenoid to Valve body. Torque screws to 5 Nm (45 in. lbs.)
3) Install valve body to transaxle.

r/tguy02 · Post by **r/tguy02** » Thu Jan 28, 2010 10:25 am

Thanks that gives me a perfect visual of what I need to get at. Wish me luck! Ha

r/tguy02 · Post by **r/tguy02** » Thu Feb 04, 2010 8:58 pm

well i'm finally gonna bump this, I'm really pissed off at the situation thats why its been a while. anyways...
I went ahead and bought the solenoid i thought i needed last week. As well as the mopar atf+4 fluid. So i get the car up on jackstands ready to change this stupid thing out, only to find something very wrong staring me in the face. Apparently the (insert 4 letter word) guy that changed the fluid and filter really..really didnt know what he was doing. He pinched the wire harness inbetween the trans pan and the transmission. Not only slightly but this thing was wrapped around one of the bolts of the pan and pinched in 3 places. So needless to say the pan didnt seal properly and fluid was leaking from there (reason why i was losing fluid) and secondly (why the lockup solenoid wasnt working) that harness went to the solenoid. So i still had to take the pan off, rip out the harness, reseal the pan, and fill it with fluid. My dad is good at soldering wire so he spliced the harness back together where it was smooshed like a pancake. i put the harness back in the car and took it for a drive. It drove perfectly, however it still throws the same code even after I reset the PCM. I don't know what's up with that

r/tguy02 · Post by **r/tguy02** » Sun Feb 07, 2010 2:00 am

Well after driving the car for a few days the cel finally went off. Hopefully it stays off. Car is still driving fine so I guess the harness patch worked. I don't see any leaks from the pan so I guess I sealed it up good. Thanks guys for your help