Conversion troubles after install

[Gscott04]

I have a 2004 preRunner 3.4 auto, and I pulled the transmission out, swapped the output shaft, and bolted up a J-shifter transfer case. everything went well until yesterday..

Yesterday Me and friends rented a bay with a lift and installed the transmission succesfully in good time, the tranny jack, lift and air tools the shop had made a 200%
percent difference in the labor. and it has full operating range, P R N D 2 1, and the 4hi and lo all engage.

The only problem is the t case (j shifter ) does not have a speed sensor either, so I tried to drive it home without it, and the truck drove fine the parking lot, but when I went on the main road and slowly accelerated, it shifted a little clunkily into 2nd then 3rd.... and wouldn't shift any higher, it just rev'd up in third gear.

So I thought it might be cause of the speed sensor, so I called the local transmission shop who has have been extremely helpful to me for this project, I have been calling and asking questions, and I called him and told him all of the symptoms
and that I didn't have a speed sensor, he said that he believes it is the cause, and because the computer
doesn't know how fast I'm going, so it won't shift into overdrive or know when to shift.. and he thinks if I can get a speed sensor
it should fix the problems...


I'm hoping that will be the solution and I'm trying to not let myself get stressed about it yet but my truck isn't driveable...

also I have a few other strange symptons, nothing on the dash seems to work I know the RPMs and MPH
is because of the speed sensor, but the engine temp needle doesn't do anything either? and also the RR DIFF LOCK light is on and i don't have the TRD never even knew I had the light... and the ECT power button doesn't work either..


SO If anyone has any advice, thoughts, insights, insults, experience, or know where I can get a speed sensor or anything else please post!!

[mosk22rte]

Is it throwing any engine codes? Did you hook up the switches in the transfer case?

And yeah, you need the speed sensor.

[Gscott04]

Originally Posted by mosk22rte

Is it throwing any engine codes? Did you hook up the switches in the transfer case?

And yeah, you need the speed sensor.

NO engine codes yet, I think I read the CEL will come on after ten miles?
I haven't driven it even a mile yet for fear
that the computer not communicating with the trans it might
cause damage, like the recall on the rav4's where there was a faulty circuit which caused the computer to go bad, lead to harsh shifts which damaged the trans..

And no I did not wire any of the switches from the T-case yet, i don't have plugs for them and was under the impression they (3) were just dummy lights...?

I picked up the sensor today from napa, much cheaper than the dealer, but they like everywhere else didn't sell it with the internal pin attached to the gear, so I had to go to the dealer for that one, its a special order for them too,
I just have to figure out how many teeth I need, 31, 32 or 33,
then call tomorrow..

[johnecon2001]

Did you swap the ECU as well?

[Gscott04]

Originally Posted by johnecon2001

Did you swap the ECU as well?

No I did not..

[drabnor]

Originally Posted by mosk22rte

And yeah, you need the speed sensor.

uh, no you dont, only for the speedo/odo to work and yes it will throw a check engine light

but it will still shift normally, you will still be able to get overdrive

my bet is you guys pinched a wire harness when putting the trans in or out

[Gscott04]

Originally Posted by drabnor

uh, no you dont, only for the speedo/odo to work and yes it will throw a check engine light

but it will still shift normally, you will still be able to get overdrive

my bet is you guys pinched a wire harness when putting the trans in or out

Are you sure? Because I was going over the FSM wiring diagrams and it said the transmission uses the speed sensor, coolant temperature, and rpms to
determine shift points... and none of those things are working right now..

well shit, let me go check under the truck and make sure nothing is pinched...



1. GEAR SHIFT OPERATION
During driving, the engine control module selects the shift for each gear which is most appropriate to the driving conditions, based on input signals from the engine coolant temp. sensor to TERMINAL THW of the engine control module and also the input signals to TERMINAL SP2+ of the engine control module from the vehicle speed sensor devoted to the electronically controlled transmission. Current is then output to the electronically controlled transmission solenoid. When shifting to 1st speed, current flows from TERMINAL S1 of the engine control module to TERMINAL 1 of the electronically controlled transmission solenoid to GROUND, and continuity to the No.1 solenoid causes the shift.
For 2nd speed, current flows from TERMINAL S1 of the engine control module to TERMINAL 1 of the electronically controlled transmission solenoid to GROUND, and from TERMINAL S2 of the engine control module to TERMINAL 2 of the electronically controlled transmission solenoid to GROUND. And continuity to solenoid No.1 and No.2 causes the shift. For 3rd speed, there is no continuity to No.1 solenoid, only to No.2 causing the shift. Shifting into 4th speed (Overdrive) takes place when there is no continuity to either No.1 or No.2 solenoid.



I did my best to make sense of that...

[fast frank]

The give away is the rear locker light being on when you don't have a rear locker.

That thing uses a ground signal to make the light come on.

You did a transmission job, and now you have an incorrect grounding situation on the engine harness.

Something is pinched, melted on the exhaust, worn through, plugged in to the wrong place, or some other variation of grounded when it's not supposed to be.

Find the problem causing the rear diff lock to come on, and you will find the problem with the other stuff too.

[drabnor]

I drove around with no speed sensor for over a year is the reason I know it will not affect the trans operation. I also still do not have any of the t-case sensors hooked up with no ill effects...

you've got something else going on

[digitalfiend]

I'm leaning torward the lack of speed sensors being part of the problem. I specifically recall researching automatic transmission "misbehaviour" and CEL's in the FSM during my auto to manual swap and I recall a section of the FSM where the automatic speed sensors and engine RPM are used to determine shift points. As far as the FSM states, if the ECU has no signal from BOTH the speed sensors (there were 2 on my 2003 prerunner A340E) then the transmission will be limited on how far it will shift. The symptoms you describe aren't exactly as the FSM detailed them, but they sound very close. If you need me to cite/quote the exact FSM section then I will when I've got the time to dig into this further. Have you put enough miles on your truck in this condition to generate any CEL's? The CEL's may help you pinpoint. For now, I wish you good luck with this. :-)

Originally Posted by Gscott04

Are you sure? Because I was going over the FSM wiring diagrams and it said the transmission uses the speed sensor, coolant temperature, and rpms to
determine shift points... and none of those things are working right now..

well shit, let me go check under the truck and make sure nothing is pinched...



1. GEAR SHIFT OPERATION
During driving, the engine control module selects the shift for each gear which is most appropriate to the driving conditions, based on input signals from the engine coolant temp. sensor to TERMINAL THW of the engine control module and also the input signals to TERMINAL SP2+ of the engine control module from the vehicle speed sensor devoted to the electronically controlled transmission. Current is then output to the electronically controlled transmission solenoid. When shifting to 1st speed, current flows from TERMINAL S1 of the engine control module to TERMINAL 1 of the electronically controlled transmission solenoid to GROUND, and continuity to the No.1 solenoid causes the shift.
For 2nd speed, current flows from TERMINAL S1 of the engine control module to TERMINAL 1 of the electronically controlled transmission solenoid to GROUND, and from TERMINAL S2 of the engine control module to TERMINAL 2 of the electronically controlled transmission solenoid to GROUND. And continuity to solenoid No.1 and No.2 causes the shift. For 3rd speed, there is no continuity to No.1 solenoid, only to No.2 causing the shift. Shifting into 4th speed (Overdrive) takes place when there is no continuity to either No.1 or No.2 solenoid.



I did my best to make sense of that...

[Gscott04]

Originally Posted by fast frank

The give away is the rear locker light being on when you don't have a rear locker.

That thing uses a ground signal to make the light come on.

You did a transmission job, and now you have an incorrect grounding situation on the engine harness.

Something is pinched, melted on the exhaust, worn through, plugged in to the wrong place, or some other variation of grounded when it's not supposed to be.

Find the problem causing the rear diff lock to come on, and you will find the problem with the other stuff too.

Ok that makes sense, I thought the locker light was quite odd, I just followed and checked all the wires plugging into the transmission and didn't find anything damaged, So I am thinking the incorrect ground is from the
three open wires where I cut off the speed sensor to extend the wiring.

And for the rear locker I have been reading through every post and article I can find and there was a thread I read through, a write up, on the grey wire mod. And someone who attempted the mod, grounded the wire coming from the locker, not the wire from the computer like he was supposed to.
and he described with the incorrect ground, his shift points were off
and he couldn't go into overdrive.
which once again backs up what your saying about the locker and the
ground issue. I'm just hoping its the wires I think it is.

Originally Posted by drabnor

I drove around with no speed sensor for over a year is the reason I know it will not affect the trans operation. I also still do not have any of the t-case sensors hooked up with no ill effects...

you've got something else going on

Ok thats good to hear about the transfer case wires I
didn't think I needed to wire those, thanks for confirming..
also, what year do you have?

I think the 03-04's may be different in regards to this because of the electronic kickdown? not sure

Originally Posted by digitalfiend

I'm leaning torward the lack of speed sensors being part of the problem. I specifically recall researching automatic transmission "misbehaviour" and CEL's in the FSM during my auto to manual swap and I recall a section of the FSM where the automatic speed sensors and engine RPM are used to determine shift points. As far as the FSM states, if the ECU has no signal from BOTH the speed sensors (there were 2 on my 2003 prerunner A340E) then the transmission will be limited on how far it will shift. The symptoms you describe aren't exactly as the FSM detailed them, but they sound very close. If you need me to cite/quote the exact FSM section then I will when I've got the time to dig into this further. Have you put enough miles on your truck in this condition to generate any CEL's? The CEL's may help you pinpoint. For now, I wish you good luck with this. :-)

Hmm yes I would appreciate this! I have the one speed sensor, the black
one with the metal nub at the end that goes next to the claw thing ( technical terms of course ) at the end of the output shaft.
I re used the one that came out of my transmission, should I swap in the 4x4 one? they both have the same plug.
I could put up pictures if you'd like if you don't know what I mean since Im not communicating very well on this one.


And thank you all for your input and ideas!


one more thing, Is it possible, there are two identical plugs on the transmission wiring harness and I switched them?

[ToyRyd04]

Answers in red

Originally Posted by Gscott04

So I am thinking the incorrect ground is from the
three open wires where I cut off the speed sensor to extend the wiring.

Any chance you have a pic of this to verify the right wires were cut?

And for the rear locker I have been reading through every post and article I can find and there was a thread I read through, a write up, on the grey wire mod. And someone who attempted the mod, grounded the wire coming from the locker, not the wire from the computer like he was supposed to.
and he described with the incorrect ground, his shift points were off
and he couldn't go into overdrive.
which once again backs up what your saying about the locker and the
ground issue. I'm just hoping its the wires I think it is.



Ok thats good to hear about the transfer case wires I
didn't think I needed to wire those, thanks for confirming..
also, what year do you have?

I think the 03-04's may be different in regards to this because of the electronic kickdown? not sure

I believe mine is identical to yours. 2004 3.4L Auto trans TRD so I may be able to help on wire colors for you.



Hmm yes I would appreciate this! I have the one speed sensor, the black
one with the metal nub at the end that goes next to the claw thing ( technical terms of course ) at the end of the output shaft.

This sensor sounds like you abs sensor and not your actual speed sensor. There should only be one speed sensor that you pulled out that looks different from a 4wd speed sensor.

If this does not make sense then look at your spindle and unbolt the black sensor from right above where you cv slides in. If this sensor is the same then the sensor you are referring to is your abs sensor.

I re used the one that came out of my transmission, should I swap in the 4x4 one? they both have the same plug.

I could put up pictures if you'd like if you don't know what I mean since Im not communicating very well on this one.
Put up pics to help solve this. I still have my old tail housing and such laying around for comparison.



And thank you all for your input and ideas!

one more thing, Is it possible, there are two identical plugs on the transmission wiring harness and I switched them?

I color coded them before I pulled all the lines off but however I would go through and check as the ones on top of the transmission (the wires) could have the same plug and could be switched around.

[Gscott04]

Transfer case plug, new speed sensor for transfer case, old prerunner Speed sensor.



Other black sensor



this is where it went on the prerunner and goes in similar location on
4wd tailhousing. next to the claw thing.

I reused the one in my prerunner. the one in the picture came out of the 4x4



Speed sensor wires I cut to extend



This is where the transfer case has a plug and ill put in the speed sensor.

[ToyRyd04]

Originally Posted by Gscott04

Other black sensor



Yeah that is you abs sensor for that part of the transmission/transfer case coupler. Prerunner and 4wd are the same.

this is where it went on the prerunner and goes in similar location on
4wd tailhousing. next to the claw thing.

I reused the one in my prerunner. the one in the picture came out of the 4x4



Speed sensor wires I cut to extend

Wires checkout, i have the same ones cut and spliced into my new vss.



This is where the transfer case has a plug and ill put in the speed sensor.

Looks like all you need is the large tooth pattern for the 4wd speed sensor. Ill snag a pic tomorrow with a tooth count.

[Gscott04]

Originally Posted by ToyRyd04

Looks like all you need is the large tooth pattern for the 4wd speed sensor. Ill snag a pic tomorrow with a tooth count.

Ok glad the wires checked out. and ok I'd appreciate it!
I ordered one from toyota this morning, it'll be here at
nine tommorow, i ordered 32 teeth, hope that works.

And yeah If this doesn't work, ill check the plugs up top to see if they possibly got switched, but otherwise my wiring harness appears to be undamaged.

[Gscott04]

Also been going over the e locker wiring diagrams,
and it looks like the speed sensor is tied in and messing with that ground as well!

[ToyRyd04]

No problem. Let me know if you run into any other snags.

[Gscott04]

Originally Posted by ToyRyd04

No problem. Let me know if you run into any other snags.

Ok I should have the part tomorrow morning along with my newly cut driveshaft (shortened) I measured about five times, told them the
length when i got there, and measured two more times when i got home and still not confident lol

But I should be able to install everything tomorrow, and I will
update with the results!!

[Gscott04]

lengthened wires one speed sensor and plugged in.
It didn't work. unplugging the battery now to reset,
then going to try and drive it.

Update:

After Driving the truck, It now shifts normal and goes into overdrive.

But

The RR DIFF LOCK light is still on, and its dim when I'm in park,
yet when I shift into gear it lights up brighter. and the O/D on off button works, and it seems to dim/ brighten the RRDL light as well.

and my engine temp, speedometer, RPM's and Odometer still do not work.

[Gscott04]

Success!!! the final problems after the speed sensor was a stupid gauge
fuse that went bad!!! Damnit!! But now everything works perfect!!

Thank you guys!!!!!!

[SafetyDang]

Originally Posted by Gscott04

Success!!! the final problems after the speed sensor was a stupid gauge
fuse that went bad!!! Damnit!! But now everything works perfect!!

Thank you guys!!!!!!

Glad to hear everything is working!

[Gscott04]

Ok, well Instead of making a new thread, should I? But Im having more post conversion problems, I have everything installed up front now, the front diff with manual hubs, I took it out wheeling already and the 4wd worked fantastic, no problems in the dirt, pulled me out of sand and up hills, worked fine, but I noticed this problem and just went out and tested it.

When I lock the hubs, and am on pavement, going STRAIGHT, if I engage 4hi,
going slow too as in >5mph, the front end gets a vibration and slows the truck down, gets worse as I press the gas, it felt very wrong and I didn't go any faster or dare to engage 4hi going any faster than I was.

You guys have any Idea's what this could be?? I really appreciate any help or any advice on what to check..

I lifted the front end up and checked what i could nothing seems to be loose..
I also fearing maybe I had a different gear ratio up front, locked the hubs and rotated the tires counting the driveshaft rotations which seemed to match the rear... but I don't trust myself on that and I could be wrong about that...

Please help

[ToyRyd04]

Did you ever check the front diff ratio before you put it in? 3.91 and 4.30's are very close to the common 4.10 when trying to do the rotating axle and counting the drive shaft spins.

What I would do first is inspect the CVs and wheel-bearings just to make sure nothing out of the ordinary is going on. (ex stuck man. hub ).

After that I would drain the front diff, after doing so you can take a flashlight and see the ring gear inside the drain hole. Take a china marker or something similar to mark your first count and rotate the CV by hand to count each tooth.(Truck needs to be in the air for this to work.) This will prove the most accurate besides separating the diff.

[Gscott04]

Originally Posted by ToyRyd04

Did you ever check the front diff ratio before you put it in? 3.91 and 4.30's are very close to the common 4.10 when trying to do the rotating axle and counting the drive shaft spins.

What I would do first is inspect the CVs and wheel-bearings just to make sure nothing out of the ordinary is going on. (ex stuck man. hub ).

After that I would drain the front diff, after doing so you can take a flashlight and see the ring gear inside the drain hole. Take a china marker or something similar to mark your first count and rotate the CV by hand to count each tooth.(Truck needs to be in the air for this to work.) This will prove the most accurate besides separating the diff.

I didn't check any other way other way than the spin method..

Ill double check everything and ill use the method for counting the teeth you recommended, really appreciate the advice, thanks.

[Gscott04]

Well it has 4.30's, at least I figured it out. fuck.



well i do have another add front diff that is 4.10's I guess ill just swap the tubes...

[ToyRyd04]

Don't feel bad man. My first diff I got at a junk yard was suppose to be a 4.10. It wasn't...however 4.30s go for a nice price up on this forum for alot of guys.

[PLC721]

yay im glad this thing is up and fully operating!