I just bought a 2000 SSEi with 205k miles that has some transmission issues. I just bought it for a work car so it would be nice to not dump a bunch of cash in it. Im located in Iowa and do all my own auto work. When I bought the car it was low on tranny fluid and slipping, and would not go into 3rd gear or fourth. Trailered car home and put some seafoam transtune in it, filled the fluid and drove a couple miles, perfomed a lot better. Back home, I drained fluid and changed filter along with new fluid. Fluid in bottom of pan was dark and smelled somewhat "burnt" but by no means close to the worst I have seen. With new fluid and filter, the transmission does not slip at all, but it still will not go into 3rd gear. Pulled trans connector on top of tranny and cleaned(wasnt dirty). Have done a quick check of the wires and grounds and did not see anything obvious, but will spend more time checking wires as I get time. I hooked up my Snap-On scanner and have three codes showing. U1040 Loss of EBCM/ EBTCM Communication
P0102 Mass Air Flow CKT
P0463 Fuel Level Sensor CKT high/open
The U1040 code I need to look into, Have looked at MAF but not tested voltage yet. Not concerned about fuel level yet. Anyone have any suggestions? Tranny toast? I will eventually get it fixed, but if someone has experience with this it will make it a lot quicker and easier. Thanks

Also, when I drove it last, I had the scanner hooked and watched the trans data as I drove. The scanner is showing that the transmission is shifting into both 3rd and 4th gear. When it is supposedly in 3rd you can pull the shifter back to 2nd and there is absolutely no change(the trans is not just slipping in third gear) When the car is in third or fourth(via scanner) the car pulls like it should when you stab the throttle but its at the RPM that 2nd gear is. Thanks again

Sounds like your 2-3 shift solenoid is stuck on.

I did the functional test on both the 2-3 solenoid and the 3-4 solenoid and they seem to work. Also when I drove it the solenoid went from OFF to ON when it should have. If you think it could be stuck on, let me know how to test or diagnose it. Any help or thoughts are appreciated, thanks

Then the solenoid is moving, the valve may be stuck. But looking at the ATSG manual that is the only thing that would prevent up shift to 3rd

Thank you, If the valve is stuck, I have to drop the tranny to access it via the sidecover, correct? My other question, if the scanner says the solenoid is "ON" does that mean it is working or just that is has power? What I am asking is does the computer receive "feedback" from the solenoid(that its working) or does it just send power to it? I am not real familiar with the electrical side of these newer automatics. I know you cannot predict what this tranny will do, but do you think its worth trying to fix it versus a $500-800 used tranny? Thanks again

SGP358 can answer that better then me.

I don't believe the valve to be stuck. It'* not common. The more common issue is a broken one way bearing in the input/3rd gear sprag causing 3rd gear to be bad. $th is most likely a stripped out (not hardened in your year) 4th gear clutch hub.

Both of these are common and almost givens in our transmissions.

4th gear
http://tripleedgeperformance.com/No_4th_Gear.html

The scanner can show that the solenoid is on electrically, but if it has failed mechanically, it will not tell you.

In 3rd gear, all the solenoids are OFF, so try this: with no power to the trans, you will have a 3rd gear start in OD and D and a 2nd gear start in 1+2. If you do not have 1 manual upshift from the 2 position to the D position, I'd say that you have internal issues.

Thanks for the replies, these are the answers I was looking for. Billboost37- I am not ruling out any possibilities, but I would assume if there was a stripped hub it would still shift to that gear but act like it was in nuetral? I'm just thinking out loud.
Sgp358- I will have to try this tomorrow night, but I want to make sure I understand you correctly. First unplug the wire loom at the top of the tranny to remove power from tranny. Next place gear shifter in 2 which should make the transmission start in 2nd gear, then manually shift it to D which should be third gear. If it does shift to third gear then the assumption would be a solenoid problem, if it does not shift to third most likely it is a hard part or internal problem. Thanks again guys.