no O/D light to pull codes

Hi,

I am working on my friends 1991 V6 4wd 4runner. the trans feels like it's always stuck in 3 or 4th. i can manually shift through the gears. The trans feels sluggish overall as well. Fluid is a bit discolored but not burnt.

The OD light never comes on so I was wondering if the light bulb or swich is the likely culprit before I start tearing into the dash and console to test them. Without the OD light i cant pull any trans codes. Do you know a workaround for pulling the trans codes w/out a functioning OD light and without a scan tool?

The engine check light is flashing code 71 - EGR temperature sensor. I guess I need to put the sensor in hot oil or water and measure the resistance at different temps? What kind of driving improvements do you get if you fix the EGR temp sensor?

OK, I removed the dash and instrument panel to put in a new O/D bulb. Now it functions and i pulled two codes:
Code 62 No. 1 solenoid valve circuitry
Code 64 Lock-up solenoid valve circuitry

edit:
surprisingly those codes were present after disconnecting the battery for an hour.

That transmission will not shift into over drive or lockup torge converter til it is warmed up and is dependent upon a good thermostat for that reason...does it warm up to halfway mark on temp. gauge in about 5 minutes?....if it takes off in 3rd you may indeed need to replace a solinoid but this may be just because it is not warmed up yet...might try letting it warm up and pulling codes off it again....either way you are in need of a tranny fluid and filter change...

There are a few solinoids that go out on these transmissions that control shift and lockup...Save money and check things out as you are and do what you know needs to be done already that don't cost you too much money out of pocket....like checking those things and unplugging wires to transmission and inspecting/ checking for loose fitting,wet or corroded connections to tranny...goodluck

The transmission does go into high gears. the problem isn't that or lack of warm up (same problem hot or cold). the problem is that the shift solenoid #1 is defective so 1st and 2nd are never available when in drive. Must manually shift into low gears to get them. When cold you should have the low gears but I never get them when in drive.

I ohmed them at the ECU. Both S1 and S3 (lock up solenoid) are open circuit. Wires are all intact. I put 12V to each solenoid and the two good ones (S2 & S3) click (I can hear it) and the two bad ones (S1 & S3) don't click. Next step is to drop the pan and replace the solenoids. Anyone done this before? The fluid has changed from red to a ruddy red/brown color, doesn't smell burnt. Is dexron III good enough or is there something called type T for toyotas? It's a Aisin Warner trans AW30-80LE (A340H).

Draining the trans only removes 4qts but total capacity is 11 qts. how to repalce more of it without a machine? do a few refills and drains?

You have done your homework/diag. good...time to call Toyota service and ask them for advice on solenoid replacement(be sure and get solenoids from Toyota)and ask them recommended tranny fluid and filter and fluid change...the torque converter holds fluid and there are also 2 transmission pans...goodluck bud

Thanks for your response but I am turning to this forum for help. The service advisors at the dealer are not generally knowledgeable. getting a mechanic on the phone is not possible. There must be someone on this forum that has tech background with Aisin Warner trans'. Maybe someone could recommend another Toyota forum?

Solenoid from Toyota are over $200 each...out of the question. I'm replacing 3 solenoids (#1, #2 and lockup solenoid). Some local trans parts suppliers have them, at much more reasonable cost (1/3rd). Toyota doesn't make them so why pay for their logo. It's a Aisin Warner trans. At over $200 each it'd be cheaper to buy a used trans! I'm not made of money.

I would first be sure to test them futher to make sure they are bad(direct test and not thru wiring to the actual solenoid)

Want a number to a service mgr. at Toyota that has an actual transmission background???1-512-392-1999 (Steve)

Might also do a search online and find someone that specializes in rebuilding Toyota transmissions for tech. help.

No offence but I highly doubt you have 3 bad solenoids and have missed something else far less expensive such as the EGR-temp sensor you mentioned or even the thermostat which your transmission depends upon for shifting and lockup signals....you mentioned earlier in posts that you checked solenoids for resistance at ECU...check for resistance as close to direct source as you can(at or inside transmission)

Personally I would back up and recheck the smaller things in the pic I believe you have overlooked/passed by....afterall as you said...you are not made of money.Either way best of luck to you bud.

Thank you for the response and valuable info. Actually only 2 solenoids turn up bad. Number 1 (S1) and number 3 (S3-lockup solenoid). My supplier (as well as an independant online info source) suggests replacing both shift solenoids (both S1 and S2) anytime either goes bad. At $40 each that doesn't seem too unreasonable. That's how it adds up to 3 (not 2) solenoids that may get replaced.

you are right i only know the problem based on measuring resistance at the ECU. Although i was directed there by two trans codes (Code 62 and 64). An open in a wire could cause the same trouble of course. i can't seem to find where the wires go into the trans so that I could test the solenoids closer. I will of course test them when the pan is off, i assume they are easy to locate/identify when the pan is dropped. I won't replace them until i test them directly. Apparently it is not unusual for the solenoids to go bad although i have no statistics on that vs open wire. BTW, I put 12V on each of the 4 solenoids at the ECU. I could hear solenoid 2 and 4 click but not #1 and 3, further confirming solenoid or wire to them failure. even if the valves clog you should hear a click.

Trans fluid is brown. AI will first inspect the pan sediments (to determine if the trans is about shot and investing more is not worth it) and then replacing the filter and solenoids (assuming old ones are bad) I will attempt a full flush by disconnecting the cooler line and running the engine while adding fresh ATF. Dexron is good enough? or do i need something specifically for toyota (type T?) or an additive to Dexron III? I understand there is no pan gasket so it should be sealed with RTV.

Thanks for the phone number, i may try to use that resource when I get in a little further (I will of course be polite :' and thankful).

Edit:
Just spoke to Steve. He says he hasn't been a tech in many years and since computer controls and FI has not really kept up from a tech perspective. nonetheless he said from a service advisors standpoint he rarely but does occasionally have a trans in the dealership with bad solenoid(s). he made the classic recommendation of changing the trans fluid before trying anything else. he did acknowledge that changing the fluid would not change the resistance (its open circuit now) of the two "faulty" solenoids (or wires to them) which definetely need attention besides a fluid change!

Note: many dealers don't see the older vehicles that start manifesting "older" car problems. Dealers seem to mostly service cars under warranty. Most non tech people have the real or perceived impression that dealers are too expensive so when their cars get 10+ years old (or less) and the warranty has expired the TLC originally bestowed on the cherished vehicle is being pushed out by economic reasoning. that's where the independant (and sometimes hack) mechanic finds its niche. i'm not saying that the techs at a dealer are any less informed on older vehicles (actually it could be the contrary) it's just that they don't see as many 'old' vehicles as many specialized independant shops do. i have also noticed that many delares dont touch trans' beyond flushes, seals and extrernal mechanical/electrical controls. Anything beyond that, they pull the trans and exchange it with a rebuilt. Afterall, working on a trans' inards is not to be taken lightly.

An earlier listing concerning reading/checking the voltage to solenoids stated it was looking for a 5 volt signal...wheather it is 5 or 12 I have no idea(just worth mentioning just in case you were guessing on voltage)

On the A-340H transmission I have seen first hand metal shavings/fragments piled up and viewable when dropping valve body...
For a sealer/gasget for pan I would use the grey RTV as it is most oil resistent and what many manufacturers use to seal front and back of intakes,oil pans,valve covers and transmission pans...red,orange and blue work too but how long is question and I know the grey is strongest and most resistent for this application.

And yes Steve is no longer a tech. but after speaking with him I'm sure you found him to be more knowledgable than most you have talked to and a wealth of common problems since he has had extensive working knowledge before present job title.

As far as what type of ATF to use...my suggestion was to ask dealer.....I just used Dextron3 and added Lucas transmission fluid treatment being that I did mine and dealership was already closed...no ill affects so far but that was MY risk.

A thermostat is cheap and easy enough to install and I have seen cases where thermostat was believed good and replaced anyways that cured problems close to yours as proper temp is important to transmission shifting,overdrive and torque converter lock up.

Thanks again for your shared info. I wonder how much "metal shavings/fragments piled up and viewable when dropping valve body" is considered acceptable. in other words if there is a lot (how much?) should I consider the trans not worth investing anymore into. you mentioned dropping the "valve body", did you mean "pan". I don't want to drop the valve body (or must i when replacing the solenoids and filter?) unless it is important to do so for inspection purposes. Will i need to replace valve body gaskets if the valve body is removed?

Sorry for all the questions...but that's how i learn.

Thanks again for your shared info. I wonder how much "metal shavings/fragments piled up and viewable when dropping valve body" is considered acceptable. in other words if there is a lot (how much?) should I consider the trans not worth investing anymore into. you mentioned dropping the "valve body", did you mean "pan". I don't want to drop the valve body (or must i when replacing the solenoids and filter?) unless it is important to do so for inspection purposes. Will i need to replace valve body gaskets if the valve body is removed?

right now the problem is that i am not getting 1st and second gear. this is true whether the OD button is on or off. The temp should have nothing to do with these low gears since they are never dissabled purposely. Once I repair and get 1st and second gear then i can start tesing for overdrive problems that take engine temp inputs to allow OD.

Sorry for all the questions...but that's how i learn.

The most stupid of all questions is the ones you never ask....

Just mentioned the shavings you may see when you drop valvebody down later if you do...no do not do that now lol.
You will see a bit of what looks like fine metal filings in pan(s) when dropped...which is normal...anything bigger then it is time to ask and wonder why...

As far as shifting goes...have you checked detent cable..sorry I have to ask since I don't know if this vehicle actually is not getting 1st and 2nd at all....if you can feel the difference and get those gears manually then it might just be your transmission (kickdown) cable out of adjustment,stuck or broken...

Sometimes there is more than one problem tied into an overall *apparent* problem.

I'm not sure what the detent cable is nor how to check it.

The trans never goes into 1st or second gear automatically (when in "D" drive). Only get them by manually shifting into the low gears. Could the detent problem cause 1st and 2nd to never occur when in "D" drive? As mentioned earlier i have open circuit ohm readings for shift solenoid #1 and #3. It should be about 10ohms. i get 10 ohms on #2 and #4 solenoid. I read that even if the solenoid fails you can bypass that system by manually shifting which is what we are observing.

He has been driving the truck without 1st and 2nd gear for almost a year now. He manually shifts into the two lower gears when he starts out especially when starting out going uphill.

I'm not sure what the detent cable is nor how to check it.

The trans never goes into 1st or second gear automatically (when in "D" drive). Only get them by manually shifting into the low gears. Could the detent problem cause 1st and 2nd to never occur when in "D" drive? As mentioned earlier i have open circuit ohm readings for shift solenoid #1 and #3. It should be about 10ohms. i get 10 ohms on #2 and #4 solenoid. I read that even if the solenoid fails you can bypass that system by manually shifting which is what we are observing.

He has been driving the truck without 1st and 2nd gear for almost a year now. He manually shifts into the two lower gears when he starts out especially when starting out going uphill.


There are 3 cables that attach to throttle valve shaft(thing at end of intake that large rubber hose attaches to)throttle/gas pedal cable(goes thru firewall),cruise control goes over to *thingy* bolted to fender well******yours may not have this******...and there is a detent cable for sure that goes down to tranny...this controls wheather transmission takes off in first or drive and downshifts for passing ect.ect.ect.....If all else fails...take it to a transmission shop after asking if they have someone that can check your detent and adjust it if nessasary(it is easy and maybe the cost of lunch or $12.50
which is what alot of honest shops charge)

Since your engine temp. controls locking up torque converter and over drive then it stands to reason that a sensor supplies this resistence you are looking for and why it is open cold....find this sensor and check connection for corrosion and test it.

Even when it is fixed he may like most 3.0L A-340H owners opt for 2nd gear starts(when a fast off the line start is needed) which will let it start in 1st and hit 2nd for a bit more take off speed...as well as hit the ECT and leaving it there for in town driving(some say they get better in town milage this way..I just like it because it performs better light to light lol)

I dropped the pan. There are no metal chunks and just a little bit of very fine fuzz on the magnets. Very little sludge in the pan. I think the trans is basically good since very little wear shows up in the pan.

I disconnected the solenoids and measured them on the bench. They are all good! I put them back in and then measured at the ECU, again they all show up good. I put 12V to them and they all click! I guess the connection at the solenoid itself was not good although it was not apparent from inspection.

I then checked the OD flash after erasing the faults. There is no more error codes. Before, i would get the error right away after erasing them even without starting up the truck. This must be because the ECU checks the solenoids for open circuit and if detected throughs a code even before running starting the vehicle.

I guess i'll put the pan back on after cleaning the already clean looking screen.

Delema, should I flush the whole system and add the Lucas (is this stuff really good?), or just put in 4 qts of dexron III 9the amount drained) and test the trans for first and second gear so as not to waste time and too much ATF in case the pan has to come off again (I sure hope not). This way if all checks out i will only loose 4 qts when i do a complete flush out of the cooling line. BTW which cooling line should be disconnected to flush so i can add ATF at the same time through the dipstick.

The trans/throttle cable appears OK.

I measure the resistance at the ECU for the two speed sensors. One came up open the other closed. No idea if this is OK and if another test should be done before closing up the pan.

Also wonder if i should clean the inside of the solenoids with brake cleaner.

Per your suggestion I will test the temp sensor(s) if i have a problem with lock up and OD later.

What does this mean and how do you make this change?
<<2nd gear starts...which will let it start in 1st and hit 2nd for a bit more take off speed.>>

<<Even when it is fixed he may like most 3.0L A-340H owners opt for 2nd gear starts(when a fast off the line start is needed) which will let it start in 1st and hit 2nd for a bit more take off speed.>>

I dropped the pan. There are no metal chunks and just a little bit of very fine fuzz on the magnets. Very little sludge in the pan. I think the trans is basically good since very little wear shows up in the pan.

Normal wear.............................................. ............................

[QUOTE=erubin]I disconnected the solenoids and measured them on the bench. They are all good! I put them back in and then measured at the ECU, again they all show up good. I put 12V to them and they all click! I guess the connection at the solenoid itself was not good although it was not apparent from inspection.

No corrision?Do they fit firmly contact/connection wise?............................................. ......................................

[QUOTE=erubin]I then checked the OD flash after erasing the faults. There is no more error codes. Before, i would get the error right away after erasing them even without starting up the truck. This must be because the ECU checks the solenoids for open circuit and if detected throughs a code even before running starting the vehicle.

No idea.............................................. ...................................

[QUOTE=erubin]I guess i'll put the pan back on after cleaning the already clean looking screen.

[QUOTE=erubin]Delema, should I flush the whole system and add the Lucas (is this stuff really good?), or just put in 4 qts of dexron III 9the amount drained) and test the trans for first and second gear so as not to waste time and too much ATF in case the pan has to come off again (I sure hope not). This way if all checks out i will only loose 4 qts when i do a complete flush out of the cooling line. BTW which cooling line should be disconnected to flush so i can add ATF at the same time through the dipstick.

Reassm., test and finish fixing all tranny problems..then flush and add Lucas treatment..it is a seal and fluid conditioner/treatment highly recommended for older transmissions..................................... ...................................

[QUOTE=erubin]The trans/throttle cable appears OK.

Adjust detent cable(kick down cable)after counting threads (to adjust back to starting point if need be) to where you take up more slack out of cable (mine is a 92 and is adjusted almost to end of threads on cable at throttle valve).Drive it and see if you can start off in a lower gear than 3rd in drive....if you have to floor it to get it to kick down tranny to take off in a lower gear then tighten it a bit more.....if it holds lower gear too long at part throttle-loosen it up a bit...ect.ect.ect................................. ...................................

[QUOTE=erubin]I measure the resistance at the ECU for the two speed sensors. One came up open the other closed. No idea if this is OK and if another test should be done before closing up the pan.

Speed sensors are important for shifting and if one is bad it could cause this problem too....test at source(sensor) and not the wiring and work your way back.............................................. ...........

[QUOTE=erubin]Also wonder if i should clean the inside of the solenoids with brake cleaner.

Only clean solenoid if sludged....40-200 bucks a pop =leave it alone if not broke to me................................................ ....................

[QUOTE=erubin]Per your suggestion I will test the temp sensor(s) if i have a problem with lock up and OD later.

**************************************************

My money is on thermostat replacement fixing your no OD or lockup(4th gear) problem and most likely detent (kickdown) cable fixing your starting off in high gear problem unless you are just not giving it enough gas to step it down as Toyotas are known for their smooth take offs....or outside chance it is your speed sensor (or more likely bad or corroded connection in wiring).

**************************************************
.................................................. ........................................

[QUOTE=erubin]What does this mean and how do you make this change?
<<2nd gear starts...which will let it start in 1st and hit 2nd for a bit more take off speed.>>


[QUOTE=erubin]<<Even when it is fixed he may like most 3.0L A-340H owners opt for 2nd gear starts(when a fast off the line start is needed) which will let it start in 1st and hit 2nd for a bit more take off speed.>>

Means just manually putting tranny in 2rd gear when taking off.

Did as planned regarding trans fluid...The truck dreives superb now. It starts out in 1st and then goes to 2nd. it would not do this before...Just for kicks I did the OD flash diagnostic. My heart fell when I saw an error code. Erased it and test drove again and trans performance remains good. Got all gears in drive and OD works great. Kickdown works although a bit loose, it takes stepping hard on the gas to go down a gear.

When I erased the error code I also read the solenoids resistance at the ECU. One of them was an outlier, it measured 45ohms and all the others were where they should be, 10ohms. later the 45ohms went down to 10 and error code didn't come back...yet. Kind of odd, could a bad connection play these games? Maybe the solenoids are acting unusual and have not completly failed again.

now I wish I changed the solenoids, if only to eliminate that variable At $240 for 3 of them i took the gamble of pasing on them...maybe it will be worth it. I did a second 5qt drain and refill and will keep my fingers crossed. i hope you understand that my problem started out as lack of 1st and 2nd gear. I still suspect that solenoids or their wiring is the entire or the main culprit.

Thank you for your generous help and can-do attitude.

edit: I did not move any wires arround except disconnect and reconnect the connectors at the solenoid. they have no corrosion since they are in the trans attached to the valve body. i gently bent the lug connectors at the solenoid for a tighter fit.

The local toyota just cleans the screen (some call it the filter) as a maintenance item rather than replace. They don't so i didn't use a pan gasket, I just used some high quality German pan gasket sealer I had leftover.

Cool beans.....the fact that your resistance goes up and down may be a sensor and not nessasarily a solenoid....don't forget your transmission solenoids are also dependent upon a signal having to do with engine temp...I bet you get 45 cold and the 10 you are looking for when it warms up...in which case just adjust the detent(kick down) cable as follows and it sounds like your work is done in tranny department.

The schematic shows each solenoid is connected directly between the ECU control and ground. When the connector is disconnected at the ECU you can measure the solenoids resistance. Nothing else is in series or parallel with it. The resistance measured is just the solenoid and the wire to it. The other sensors are connected to the ECU as well but whatever state they are in will not change the resistance measured for the solenoid. This is not to say that the other sensors will not effect the trans and the solenoids but they are not in the electrical circuit when the ECU 26 pin connector is disconnected for measuring the solenoid's resistance.The other sensors are processed by the ECU which in turn can turn on or off a solenoid. The solenoids are either on or off, nothing in between so why would there be a resistive element in line with them?

Of course if you have a schematic that shows some other sensors (temp, speed etc) in line with the solenoids I would very much want to know more about it.

The schematic shows each solenoid is connected directly between the ECU control and ground. When the connector is disconnected at the ECU you can measure the solenoids resistance. Nothing else is in series or parallel with it. The resistance measured is just the solenoid and the wire to it. The other sensors are connected to the ECU as well but whatever state they are in will not change the resistance measured for the solenoid. This is not to say that the other sensors will not effect the trans and the solenoids but they are not in the electrical circuit when the ECU 26 pin connector is disconnected for measuring the solenoid's resistance.The other sensors are processed by the ECU which in turn can turn on or off a solenoid. The solenoids are either on or off, nothing in between so why would there be a resistive element in line with them?

Of course if you have a schematic that shows some other sensors (temp, speed etc) in line with the solenoids I would very much want to know more about it.

Then I would clean and check grounds to sensors....best test is still at sensor itself as it *e-lemon-ates* and bad wiring or connections.

The resistance element would be a temp sensond such that sends a signal to ECU to lockup or let over drive kick in and such is what I meant...or wired inline as some I have seen...

I have worked on all types and over many years.....don't have the schematic myself and was wondering your source and if available lol

nothing left to check regarding the trans since it's working fine, for now at least. If things go bad I'll check some sensors before removing the pan again!

i have shop manual details for many (not all) of the important systems on your truck. Private message me if you're interested.

This article although about Volvo transmissions does talk about the Aisin Warner found in a 4runner. http://www.babcox.com/editorial/ic/ic40238.htm

He writes:

<<Solenoid valves (SL, S1, S2, STH), see top photo, sit in the hydraulic system valve housing, which is located beneath the housing cover on the transmission. Solenoid SL regulates the torque converter lock-up function, and valves S1 and S2 control the shifting. These valves are activated by the transmission control module, as is solenoid valve STH, which controls the transmission line pressure.

If there is a code found for an open circuit in one of the shift solenoids and erratic shifting (starting off in second or third gear), it is possible to replace them with the transmission in the car. I recommend replacing both S1 and S2 solenoid valves even though the ohm readings are in specification (10-15 ohms), as I have seen the solenoid valves work intermittently.>>

Sounded like you still needed to tighten detent/kickdown cable so it would downshift for passing without having to *floor* it.

Glad I was able to help and bookmarked site in your last post...enjoy the ride bud .