P0770 Fixed?

[LAKER-FAN]

Wassup Toyota Nation Fam. I've been lurking on this forum for a while, and it seems like you guys know your *ish. Let see if you guys can help me with this one..

My wife has 03 corolla with 84K and we've NEVER had any problems. Today I got code: P0770. The readout says probable causes are: Shift solenoid stuck open or blocked oil passage or lock up clutch failure.
I did a search and couldn't find if anyone had success fixing this issue.
Have any of you guys had this code serviced?
Do you guys think I have a bad ECM? If I do The TSB says I'm out of warranty

Any thought or suggestions? thanks in advance

[dorman68]

Sorry to hear about your issue. The PCM was more of an issue with the 05-06 Corollas regarding the transmission shifting and trouble code issues. The 00-04 models seamed to have an internal shift solenoid problem due varnish building up from old transmission fluid. I have helped a relative out with a 2003 Toyota MAtrix withthe same issue, he got lucky, we changed out the fluid twice and the problem never came back.

[mikered30]

Check the fluid level and condition ( dark or burnt smelling) then might look at the speed sensor and then the shift solenoid. New fluid is cherry red in color. When was the last time you changed your tranny fluid? Ever? You can do a couple of drain and refills or a flush of the fluid. Try adding a bottle of lubegard Red when you do your change. That stuff is the best. You can go with T-IV fluid from the dealer or mobil 1 or maxlife ATF, as long as the bottle says T-IV compatible on the bottle, you will be ok.

The drain plug is 14 mm, just like the oil plug. You will want to get a new crush gasket for the plug. Be careful not to strip the plug, it is very short for some reason. Not sure if you have NAPA or carquest in your area, but they usually carry the lubegurd red bottle. That stuff really works, assuming it is not a mechanical problem. Might want to go with a synthetic fluid, assuming it is just a varnish issue, the OEM fluid is not syn, even though they price it out like a syn product. A couple of drain a refills (3.5 qts or so per drain) with the lubegurd red on the last refill maybe the way to go. If you cant do the work yourself, a shop can do the flush, but make sure they use the lubegurd red.

[hughesjasonk]

do a tranny flush then monitor. it could just be a stuck valve. if it doesn't unstick you will have to replace the valve body

[LAKER-FAN]

So i drove the car around for a few miles today and the CEL went away. I hope that it doesn't return. I decided to that I'm going to do a couple of drain and refills and add some Lubegard. @mikered30 is the lubegard that you recommend Part #: 60902?

[mikered30]

The lubegard red is found here:

Amazon

Amazon

It is that part number, 60902. Transmission shops usually carry it because it works.

If you do 2 drain and refills, while driving in between to mix, you will get 71% of the old fluid out as you cannot drain the converter. A single drain and refill is 3.5 qts (when hot) and the total capacity of the entire trans system is 7.8 qts. Put back in what you take out assuming the level was correct before. Check the level when you have been driving over 20 min on the highway, with the car at idle on a flat surface.

There is not much info on P0770. After you change the fluid let us know how it went and the condition of the old fluid. Did you inspect the fluid yet? How did it look? It would be very costly if it is a valve or ECU issue.

[hughesjasonk]

Originally Posted by mikered30

The lubegard red is found here: http://www.amazon.com/AUTOMATIC-TRANSMISSION-FLUID-PROTECTANT-OZ/dp/B0007ZAJRM/ref=sr_1_1?ie=UTF8&qid=1303616622&sr=8-1-spell


It is that part number, 60902. Transmission shops usually carry it because it works.

If you do 2 drain and refills, while driving in between to mix, you will get 71% of the old fluid out as you cannot drain the converter. A single drain and refill is 3.5 qts (when hot) and the total capacity of the entire trans system is 7.8 qts. Put back in what you take out assuming the level was correct before. Check the level when you have been driving over 20 min on the highway, with the car at idle on a flat surface.

There is not much info on P0770. After you change the fluid let us know how it went and the condition of the old fluid. Did you inspect the fluid yet? How did it look? It would be very costly if it is a valve or ECU issue.

check it after the motor is over 190degrees F and the motor is running. btw i wouldn't drive it anywhere while you're getting it up to temp to check the fluid. just let it idle. once you have the proper level then drive it.

[LAKER-FAN]

I drove the car approximately 30mi today and the CEL has not returned. I checked the fluid and the level is good but the color is pretty dark. The fluid is the stock one. Thanks for the recommendations and suggestions. I'll Keep you guys posted. How many miles do you guys think I should drive before the second drain and refill?

[hughesjasonk]

Originally Posted by LAKER-FAN

I drove the car approximately 30mi today and the CEL has not returned. I checked the fluid and the level is good but the color is pretty dark. The fluid is the stock one. Thanks for the recommendations and suggestions. I'll Keep you guys posted. How many miles do you guys think I should drive before the second drain and refill?

if it's dark already i would change it now with a new filter.