nomotivs

Hi. I was wondering if anyone might have some insight into my transmission problems. I have a 97 4runner SR5 V6 (96,500 miles) with the auto tranny (A340H). I'm getting codes P0753(Shift Solenoid A Electrical), P0770 (Shift Solenoid E Malfunction), and P0773(Shift Solenoid E Electrical). Periodically it seems like the transmission isn’t shifting back down when I come to stop. When I go to accelerate from a stop sign or light it’s very slow to get going. It almost feels like its slipping but I don't think so. I can shift into L and get going fine. I've also noticed that reverse seems to have similar problems from time to time. The problems started occurring a couple months ago but would be infrequent and the check engine light would turn back off after not occurring for a while but in the last week it has started to happen about half the time. I thought it might be a Solenoid and I would just try and replace it but after pulling multiple codes I'm not really sure where to start. If anyone has any insight or recommendations I would greatly appreciate it! Thanks.

edzo

check for shorted, worn, cruddy wires between ecu and tranny.
unhook the wire loom, then reattach

check for shorted, worn, cruddy wires between ecu and tranny

that and a voltmeter at the ecu on the sensor pins to isolate an electrical malfunction
...a full manual will tell you what to test

you will have to drop the tranny pan to test the solenoids, or stuck solenoid.
and drop the propeller to test speed sensor

to get away with it easy, have a power tranny flush and see if it is just gummy atf. other than that, you are looking at some downtime to diagnose

toytech76

a flush wont fix your problems. Dirty or bad fluid wont trip those codes. My guess is shift solenoids a and e are bad or stuck. I would replace them. Your trans probably is slipping when you take off so be very careful on how much you drive. You could wear out the clutch packs and really cause yourself grief.

edzo

old atf fluid doesn't usually stick solenoids ? what causes them to stick, or do they just wear out ?

what does old atf fluid usually end up doing...?


my transmission kung-fu is weak

toytech76

its an internal electrical issue that makes them go bad usually. Hence the elect malfunction code

nomotivs

Thank you for all the help and suggestions so far! Are solenoids "A" and "E" easily accessible by just dropping the pan? If anyone can point me towards a diagram of pictures that label where the particular solenoids are located that would be great. Thanks.

toytech76

im not sure if you need to pull out the valve body as well. Check that out before you get too involved with it

edzo

yeah

search for a post I made which links to another thread with a link
to a full tacoma 2000 manual which has that transmission type in it

97ltd4x4

With that many open/short codes.I would inspect the connector and wires where it plugs into the trans..maybe corroded from water? Or have you had the pan down recently? the wires could have been pintched...It is possible that both solinoids did go electrically open.You can test that from an OHM check from the ECM connectors.You would need a factory manual and a good meter to test.

I do believe that you can change the solinoids after you drop the pan.No need to remove valve body.

mt_goat

Yes that's correct, at least on the A340F, you might need to remove the ATF filter though, but that's no bigge.

Here's writeup on removing a valve body on a A340F (even though you don't need to) it will show pics of the 3 soleniods on the valve body.

http://members.cox.net/mgriese5/Level10.html

The A340H should be similar.

Here's another thread on the subject:
https://www.yotatech.com/forums/f2/4...cation-137360/