I have a 2006 LT. a month ago I drove through a few inches of water at Walmart. When I went to leave, the car delayed shifting out of first, and when it did it was a hard shift. 2nd gear wasn’t much better. I drove home about 5 miles and on the way it seemed to mostly clear up. Next morning I drove back to town and it seem to be fine. On the way home the CEL came on and it began to again not shift quite right but not a bad as the day before. Got home, checked for codes and got 2. P0700/P0751. Indicating a Solenoid “A” problem. After doing some research I did a TCM reset, ran a ground from the TCM to the strut mount. The codes were cleared by doing that and it drove fine for about 20 miles, the CEL came back. I have taken it to four different mechanics, have spent a bunch of money for them all to tell me something different. No water or wiring harness issues were found. Because it seems to work fine after clearing the codes, and worrying about doing damage, I have done that before every garage trip. Now, even when the CEL comes on it seems to be shifting okay. Could someone please help me understand this. All the places want thousands to do their fix, and they all involve changing that solenoid or the whole transmission. It seems to me if something is broken, it’s broken. How does that solenoid work fine, and then not because a light came on. I can’t help but feel it’s something other than what they are telling me and I’m going to throw more money at a non existent problem, and still the one I have. I would really appreciate any input.

 

Because when you clear codes the testing has to start from step 1A, until the test passes the computer runs in open loop, no feedback just static data.
Just replacing the solenoid is not that huge a deal about 6.3 hours labor and about $28 for the part. That is with pulling the transmission, but it can be done without pulling it.
Most shops don't want to be bothered with repairing 20 year old transmissions so they either over inflate the problem or misdirect you.
Are you sure those are the only codes? Might be just some water got into the electrical connectors.
What did you do to "reset the TCM"? Facebook is trying to burn your car down.

Get rid of that stupid ground wire, it is dangerous and totally not needed. It just makes it easier to completely fry the TCM when some body (idiot) tries to jump start the car.

 

You didn’t get the right answer about the fix for those codes, the shift solenoid issue requires replacing the solenoid which involves lowering the engine cradle and transmission to remove the side cover and remove and replace the solenoid, I suggest you replace the solenoids

good information in this thread, even a video

https://www.chevyhhr.net/forums/driv...d-61313/page2/

 

After spending too much money on different diagnostic efforts with locally available garages, I took it to a reputable transmission shop in a large city. After the last time of clearing the codes, and driving now maybe 50 miles, it shifts fine and the CEL has no come back on. They told me they tested the solenoids, and they are fine and they suspect the problem is clutch debris moving about in the transmission. Would it possibly be removed by a fluid change? Or would that be a bad thing to do?

 

A change would get rid of some debris. No matter what any book tells you get Dexron VI to refill, there are many brands just look at the label.
And a new filter!

 

Thanks, I much appreciate the reply.