Just happened suddenly 2 days ago. Started car in the morning, drove down the street and it will not shift out of 1st in drive. No CEL and yes the light works fine. Tried it in low and 2nd but no change. OD on or off made no difference. Fluid old but full. Read through the downloaded manual and tried the test of disconnecting the plug from the 2 internal solenoids and a test drive shifting manually. It shifted just fine both up and down, no problems. It did light up the CEL then as the book said it would. Connectors look clean and no obvious wire issues. I read just about everywhere that if it is my 1-2 solenoid it will throw a code and light the CEL but this did not. Speedo works just fine as does the tach so probably not the speed sensor. The next item the diagnostics chart say to suspect is the ECM which I have not tested yet. I have new fluid, screen and gasket coming and I will try to test the solenoids while I am in there and clean them up if need be. I read they might have varnish on them and be sticking part way but I would think this would light the CEL but I don't really know. I have had the car 3 years and, this past year due to covid, I only drive it about 3 times/week just to keep the battery (6months old) charged up and everything working ok. I live alone here so does anyone know if it would hurt anything to drive it with the solenoid plug disconnected and manually shift it like I did on the test drive? I might need to go out to a parts store somewhere along the way while fixing this. The car has always driven and shifted perfectly both up and down and this problem came on instantly so...maybe that is a clue? I would really appreciate any advice or suggestions you knowledgeable folks might have. I have been working on this 2 days trying to figure out the problem and, unless its the ECM, I am stumped. Thank you.
Bill

 

Too early to be stumped! Suggest more research.

Some code should show up. Have you checked for pending codes? However if no codes would move on.

The following is what I might do.

You can buy a rebuilt valve body online with solenoids from around $300. A used ECM can be had on Ebay for a very low cost. Get the exact same part number as the one on the old one.. Sometimes ECM's do fail but its uncommon. If you can get a cheap ECM then might change the old one out as its worth a diagnostic time saving shot..

The manual should have a detailed testing procedure for the solenoids and ECM.
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The wiring diagram section has an explanation of how the electrical system works for the trans shifting.

Read up and run all the tests. You should be able to do many tests with the pan still on the trans. Do as much diagnostics with the trans pan on as possible.

With pan off can check for debris. The manual has info on removing and testing the solenoids when removed. Get a neck type flashlight and dental mirror to look into the solenoid passages after a solenoid is removed. If you can access an air compressor you can do more tests.

If your going to change the fluid do it all. The internet has videos on how to do this using the trans own oil pump. Use a Dexron III replacement. Costco used to sell Chevron MD-3 ATF at reasonable prices and may still do. A complete change will take 8-9 quarts to clean out the old fluid. The pan holds around 2 quarts with the rest in the toque converter.

If the fluid has never been changed then valve body issues could be a problem. A BIGGER problem is the trans internal parts can fail with never changing the fluid and this DOES happen. However the trans shifting manually appears to point to an electrical or computer problem.

The manual states if the electric shift fails then shifting reverts back to manual. Suggest removing the electrical plug then keep driving manually.

Run some tests and post back.

If all else fails and the tests are OK might change out the valve body.

 

Thank you for your detailed reply. My OBD II reader arrived yesterday and I only had 3 codes, two of which (PO 753, PO 758 shift solenoids) I caused by pulling the connection from the trans to do my manual shifting test as the trans service manual said would happen. The other code (PO 440) was something about the evap system/gas cap leaking and it was a pending code and never tripped the CEL. So, here is my plan. While I am waiting on the gallon of trans fluid I order online (Castrol Transmax Dex/Merc) and my new screen, gasket and 10mm hex socket, I am going to make up a test lead from some wire and a 12 volt fuse. I am going to hook up to the battery and another wire will go to ground on the transmission and I will then touch the + wire to each of the 2 terminals in the transmission connector and listen for the "click" of the solenoids. (I saw a Y.T. video on this and you can hear the clicks when the engine is off) IF they both work ok, then I will check the continuity of the wiring from that connector back to the ECM. Then I am taking my scooter to the Shell station at the end of my road and buying 3 quarts of trans fluid and I am going to drain out what I can from the pan trough the drain plug. I am going to add 16 oz of seafoam transtune and top off the fluid with the cheap stuff. Some mechanics say to drive it for 100 miles and then drain, but I will drive it up and down my road shifting manually and let it idle for a while then drive some more, etc. Then, when my gasket and other stuff arrives this weekend I will drain again...pull the pan, change the screen, inspect what I can, put back together and fill with the Castrol. (I know I am only replacing about 1/3 of the fluid but do not want to mess with possibly breaking one of the trans lines as they are very old) Then, I will see if it is fixed. If not, I will drive it around some more. If still not shifting I think I will see what my ECM tests show and I might just buy one from ebay like you suggested. If the serial numbers match mine then I should have no issue with needing to have it programmed right?) If that still does not do it then I will have to save up for the rebuilt valve body and solenoids and install them. Do you have a good source for those? I do not expect miracles from the seafoam but many folks have posted that simply changing their fluid and screen several times fixed a no upshift issue after a while and others say that the seafoam transtune cleans it up faster than just the detergents in the new fluid. (It supposedly removes varnish that has built up over time. Later, I will buy another gallon of Castrol and drain and fill again 2 more times. It will still not be as good as your flush method but, it will still get rid of most of the old fluid I would think. (The seafoam folks say it is safe to leave in the entire time between trans fluid changes so hopefully, any left behind will not hurt anything.) I am trying to do this from cheapest to most expensive as I think the remaining possible causes all have about the same probability of being the problem. Oh, and one other mechanic online suggested that I test all the wires in the connector for the gear selector/neutral safety switch because he had the exact same problem with no upshift and it never lit his CEL either. He had a broken wire and when he repaired the wire, it upshifted fine again. So I am checking that today as well. Again, I really appreciate your taking the time to respond to me here and, I certainly will post any and all results as well. I read a lot of the Toyota forum and Camry forum posts and get interested in someone's problem and am following it trying to figure out the cause is and wondering what it might be but...then, they never post what it turned out to be or what happened and that is not a good thing to do. Many folks, like me, learn from reading about vehicle specific issues and how to repair them. I was actually reading a series of posts on trouble shooting a power window issue which was interesting and, all of mine worked at the time. Shortly thereafter, my passenger window quit working. (Yes, in the down position of course) So, I went back and pulled up those posts and found my motor was bad and better yet, I even used the same supplier they suggested and got a new regulator complete with new motor for $25 and free shipping. (The dealer wanted over $250 just for the part and would need to special order it) 3 years and my window still goes up and down just fine so yes, I do appreciate these forums and the people that share their knowledge and information and maybe someone will be helped by reading these posts on my problem.
Bill

 

Could be a wiring issue or bad ground connection. One terminal of the solenoid goes to ground.

Not a big fan of adding chemicals as there can be potential issues. A concern is if this varnish gets loose where does it end up?

There are rubber hoses connecting the oil cooler to the trans. Remove the oil return hose at the trans (this oil ends up in the trans pan). Place the hose in a 1 gallon transparent or clear container. Drain and refill the trans. Add the same amount of new oil that drained out.

Have a friend start engine and watch the fluid come out until about 2 quarts then stop engine. Do another drain and refill, then repeat the pumping out process.

After 8-9 quarts the fluid will be clear. On the last refill check fluid level and adjust to proper level.

This is the easiest, safest and more complete DYI method of changing out ALL the oil.

As long as you get the exact same computer part number you need only swap parts.

Rebuilt and used trans bodies are sold on the internet.

 

Thanks. You are right. Since there is only one 12 volt wire going to each solenoid, they are getting their ground through the transmission case which is grounded to the car and therefore back to the - battery terminal. (Unless the trans is ground by being bolted to the engine which is already grounded?) All the other things could be grounded just fine but if the trans ground is messed up, then the only things nor working would be the solenoids and this may not generate a code of any kind. Excellent suggestion. I will track down the trans ground and check it out. I am not crazy about adding the seafoam to the trans either and, at least I will have it and I can always use later. If it is something like a bad trans ground or ECM I don't want that stuff swimming around in there either. I live in an apartment complex and we are not allowed to work on cars here. (They have nailed me more than once trying to do a simple, quick thing like swap windshield wipers. So, I have to do all my work on on the road in a streetside parking space. No electricity available and I have to be careful not to get my legs run over while under the car. Not a big deal, I did my oil pump and timing belt work this way and valve cover gaskets, etc. I just don't want to risk breaking off one of those cooler hoses as both are hard as rocks and I know I would break it if I tried to remove. Yes, they need to be replaced and I will get to that...eventually...ha ha. Thanks for the info about the ECM swap. I went to a site selling them to get a price and they said, as part of their sales pitch I am sure, that if you do not buy a used unit from them then the one you get will need to be programmed at the dealer and it will cost a lot more, etc. turns out, they do not carry ones back as far as 1999 anyway. Hopefully, I will not need a valve body but, if I do, it is good to know I can get a rebuilt unit. Again, I appreciate your help.
Bill

 

As you state would be checking for electrical issues.

Does the car have an immobilizer anti theft system as in having a chip in the key and red light on the dash? If so then changing the ECM may require some kind of programing or the computer will not recognize the old keys.

Trans pan drain and refills should be OK.

 

No, no key fob or chip in the key. The key is just plain steel. Well, after checking over my connectors as best as I could, I put them back on and made sure they were totally seated and, just for the heck of it, I went for a test drive and...IT SHIFTS FINE AGAIN! So, I have/had either a connector not fully seated, or a wire that is partially broken and moving it improved the connection. I have had this car for three years and no one has even touched either of those connectors at all. (I am the only one that works on this car) Engine mounts are good so there is no flexing. Maybe the person that last put on the connectors did not seat them well and it took all this time for them to vibrate loose to the point the connection was weak, but not broken. This would explain the shift solenoids not working and why the CEL did not light up I think. (Maybe they moved, but not enough?) I am carrying the special long nose pliers I used to pull the connectors off with me just in case it is a broken wire and happens out on the road somewhere, I can just pull the solenoid connector off and drive home manually shifting. All my stuff arrives today so I will still do the drain and filter screen change along with several more drains/fills as we discussed. Also, no Seafoam Transtune will be added but I will keep it around just in case. I am very happy right now and, I want to thank you for all of your great suggestions and very helpful information. I love this car. A lady I worked with last year had the same year as mine (99) and she had a little over 500,000 miles on hers. Hopefully, mine will keep going for a long time. Thanks again.

Bill

 

Well, it happened again BUT this time, when it would not shift out of low, I got the CEL illuminated right away. Also, I lost both the speedometer and the odometer. I was not far from home and I drove slowly for about another minute then the speedo and odometer came back on and it shifted fine again. I checked and the only code there was for the VSS so I ordered a new one. I watched a couple of videos on how to replace it. It is in a hard to reach area and even though the manual says to remove that airbox, etc. the videos all showed it being done from under the car so I am going to try that way. It is too much of a coincidence for this to not be related to the first time this happened but since I still had the speedometer and odometer and no CEL, I never considered the VSS as the possible cause. It could also be the VSS connector and/or wires so I will check those while I am under there. The new unit was not that expensive and I will test the old one when I remove it. If the connector is bad, does anyone have a good source for Toyota connectors used in the 1999 Camry?

Bill

 

Search on on "1999 camry VSS harness plug"

 

Thank you very much.

Bill