2wd Automatic to 4wd Manual Swap - Need some help/have some questions.

[TheManOutside]

I've always wondered if you could keep the automatic ecu, find a way to trick it into thinking there were shift solenoids, and use the diff from a manual hub Tacoma. You'd have to lock the axles every time, but it would solve some other problems

There is a way to use the automatic ECU by tricking it into thinking you're always in neutral, however I don't know how to do this and I'm pretty sure you get a CEL. I'm not sure what you mean about locking the axles every time. Would it be easier for me to use a Tacoma front diff and other parts?

 

[TheManOutside]

:bump:

I have a question, this one is much more important than my last 100, so please respond if possible. Keep in mind I almost have no idea how automotive wiring works, so this may be completely different? Idk. Either way, I drew up this weird little drawing thing trying to show what I want to say.. I want to know if it's possible to "cut and paste" wires from the donor truck onto my current harness to avoid removing the whole thing and rewiring my whole truck..

Here's my drawing:

Is this even possible/relatively possible? Thank you!

 

[jmsdad]

Easier and less headache to use the manual harness with it's matching ECU or re-pin the auto harness to use the manual ECU.

I wouldn't want to cut the harness and splice in the way you've illustrated...one being that after the soldering and heat-shrinking the whole harness will grow to double it's size at splice/solder area.

Here's some more reading for you.....


http://www.toyota-4runner.org/3rd-gen-t4rs/180875-repinning-auto-harness-use-manual-ecm.html



It took me about 1 hour to do my re-pin conversion chart and another 45min to actually re-pin the harness.

 

[jmsdad]

Just thought of something... If I were to swap my transmission with the R150F, would I still be able to drive the truck without any 4wd parts installed (no connected front diff, driveshaft, etc.)? Just curious because I think it would be nice to test the transmission before going further onto 4wd, but if I must I must.

Of course you can! I've been doing that for the last 1600miles or so

 

[TheDurk]

Easier and less headache to use the manual harness with it's matching ECU or re-pin the auto harness to use the manual ECU.

I wouldn't want to cut the harness and splice in the way you've illustrated...one being that after the soldering and heat-shrinking the whole harness will grow to double it's size at splice/solder area.

Here's some more reading for you.....


http://www.toyota-4runner.org/3rd-gen-t4rs/180875-repinning-auto-harness-use-manual-ecm.html

It took me about 1 hour to do my re-pin conversion chart and another 45min to actually re-pin the harness.

Yep. Either repin or rewire the engine with the right harness. What you say IS possible in theory, but I wouldn't want to do it or help anyone who did. Just doing it on paper (with wire colors and locations, pin numbers, etc.) is a gargantuan task. Then executing would be a bear, and splicing, even for those that are very good at it, is prone to failure. Finally, once done, eventual troubleshooting would be a nightmare.

 

[TheDurk]

Just thought of something... If I were to swap my transmission with the R150F, would I still be able to drive the truck without any 4wd parts installed (no connected front diff, driveshaft, etc.)? Just curious because I think it would be nice to test the transmission before going further onto 4wd, but if I must I must.

Oh, and here's Jon's build thread.
http://www.toyota-4runner.org/3rd-gen-t4rs/145595-bawlzdeep-build.html
He used his automatic ECU I'm pretty sure, has the CEL on but he took the bulb out, and I'm assuming he also passed emissions (he also lives in California).

Yeah, I'm not so sure about that. He doesn't have a front plate (I thought Cali. required them) and the only shot I saw of the rear looked like a Georgia peach on there. I know it wouldn't pass like that in NY or NJ, so I'd research that a little more if I were you.

You can run the trans without any of the front stuff connected, no problem. I ran mine with the front DS out for a month because I ran out of time on my last clutch job. Key question is will you have a TC and 4wd rear shaft or will you try and mate just the 5-speed trans to your 2wd rear shaft? Just think about if you will have a trans/TC or not TC/driveshaft train that works together. I assume the 2wd shaft is longer because of the TC.

 

[IBallEngineer]

Yeah, I'm not so sure about that. He doesn't have a front plate (I thought Cali. required them) and the only shot I saw of the rear looked like a Georgia peach on there. I know it wouldn't pass like that in NY or NJ, so I'd research that a little more if I were you.

You can run the trans without any of the front stuff connected, no problem. I ran mine with the front DS out for a month because I ran out of time on my last clutch job. Key question is will you have a TC and 4wd rear shaft or will you try and mate just the 5-speed trans to your 2wd rear shaft? Just think about if you will have a trans/TC or not TC/driveshaft train that works together. I assume the 2wd shaft is longer because of the TC.

Yes California requires it, but no one cares. I haven't EVER had a front plate on my LC. And that's 19 years! Pre 2000 vehicles can be smogged fairly easily with bypasses and tricks because they don't connect to the ALDL during the test, pre OBD doesn't scan at all but that doesn't apply to 3rd gens. Post 2000 runs the test with live data, very hard to cheat.

To the OP, where in SoCal are you, I know a guy who can help you with the wiring! ME!

I'm solving a Cadillac nightmare at the moment, the dealer gave up, so did the independent GM specialist. Of course they just don't have time to devote to nightmares, and I do. ??

:crazy:

 

[jmsdad]

Oh, and here's Jon's build thread.
http://www.toyota-4runner.org/3rd-gen-t4rs/145595-bawlzdeep-build.html
He used his automatic ECU I'm pretty sure, has the CEL on but he took the bulb out, and I'm assuming he also passed emissions (he also lives in California).

Just looked thru his thread and he still has Florida plates. Could very well be that the vehicle is still registered in Florida as he is still serving in the military and is stationed in CA?

Also some counties in CA don't require biennial smog checks. So if you can get by the initial inspection you're in the clear.

 

[TheManOutside]

I'm pretty sure you don't have to have front license plates in Cali (or at least matching with the back) since I know some people who have cars with UK front plates. Oh well! And I thought Jon was from CA, I should've looked at his plates.. :rockthrow:

To the OP, where in SoCal are you, I know a guy who can help you with the wiring! ME! :crazy:

I live near San Juan. You're about an hour away if you're in Covina.. I wouldn't want to make you drive all the way here to do some wiring :laugh:

Easier and less headache to use the manual harness with it's matching ECU or re-pin the auto harness to use the manual ECU.

So, I can just re-pin my current harness so I can plug it into the manual ECU? How difficult is this, and I thought there were other cables that are not on my current harness but are on the donor (cables for 4wd for example)?

 

[TheDurk]

I live near San Juan. You're about an hour away if you're in Covina.. I wouldn't want to make you drive all the way here to do some wiring :laugh:

So, I can just re-pin my current harness so I can plug it into the manual ECU? How difficult is this, and I thought there were other cables that are not on my current harness but are on the donor (cables for 4wd for example)?

There are. You will have to create or import everything in the following diagram for a J-shift TC. This is for a '99, but this circuit changes very little, if at all. (Push button is much worse.) You can leave out the part for the diff/ lock. as you won't be doing that, and the parts that are for A/T only. You might even find some of those wires in your existing harness, just not connected.

But it might not be THAT hard to use the existing harness and import the 4wd wiring separately. The part in the engine bay is only the four wires to the VSV's that come from the relay in the kick panel and the wire to the front diff position switch. There are three wires that connect to the ECU.

In any case, if [MENTION=102597]IBallEngineer[/MENTION] says they won't scan a '97, then it is certainly an approach worth looking at. You can trust that guy. I'm surprised, though. NY and NJ scan all OBDII cars so back to '96. Rare that Cali. is less stringent.

 

[TheManOutside]

There are. You will have to create or import everything in the following diagram for a J-shift TC. This is for a '99, but this circuit changes very little, if at all. (Push button is much worse.) You can leave out the part for the diff/ lock. as you won't be doing that, and the parts that are for A/T only. You might even find some of those wires in your existing harness, just not connected.

But it might not be THAT hard to use the existing harness and import the 4wd wiring separately. The part in the engine bay is only the four wires to the VSV's that come from the relay in the kick panel and the wire to the front diff position switch. There are three wires that connect to the ECU.

So basically, the only wires I would need to use (that I might not have) are ones that plug into the diff and ECU for 4wd, and the ones that plug into the ECU for the 5 speed (which would be re-pinning my current harness), correct?
How would I attach the wires I would need to my harness if my current harness doesn't have them? Also, how would I know if my current one has them or not, where are they usually located? Thanks!

 

[IBallEngineer]

In any case, if [MENTION=102597]IBallEngineer[/MENTION] says they won't scan a '97, then it is certainly an approach worth looking at. You can trust that guy. I'm surprised, though. NY and NJ scan all OBDII cars so back to '96. Rare that Cali. is less stringent.

Let me clarify, they do scan all OBD vehicles to check for monitors and current codes, but they don't run the test with live data, like the 2000+ vehicles do. So you can have a monitor for non emmisions failure and still pass. Or you can do some other tricky stuff.

:blah:

 

[TheDurk]

So basically, the only wires I would need to use (that I might not have) are ones that plug into the diff and ECU for 4wd, and the ones that plug into the ECU for the 5 speed (which would be re-pinning my current harness), correct?
How would I attach the wires I would need to my harness if my current harness doesn't have them? Also, how would I know if my current one has them or not, where are they usually located? Thanks!

Makin' me work, huh?

Doesn't look good. Both the main cowl wire harness and the main engine wire harness are different p/n's in 1997 . The cowl is different between auto and manual and the engine is different between 2wd and 4wd. So you would have to use a new split plastic loom and zip-tie it to your existing harness to add these wires. You would still want to get the connectors off a donor because Toyota only sells empty connector housings and repair wires with the pins on the end and that gets expensive.

 

[St Runner]

As others have already said you are going to have to find a donor vehicle to do this properly. Same year and same engine as yours. Not only will you have all the parts you need but you will have a template for how it all goes together. I pulled a perfectly good auto transmission out of my 97 last month and put a R150 in it. I would not of even considered it if a wrecked 97 had not fallen into my lap. Yours is going to be even more difficult because you want 4wd. Do your research and start looking for a donor, you will not regret it

 

[TheManOutside]

Makin' me work, huh?

Doesn't look good. Both the main cowl wire harness and the main engine wire harness are different p/n's in 1997 . The cowl is different between auto and manual and the engine is different between 2wd and 4wd. So you would have to use a new split plastic loom and zip-tie it to your existing harness to add these wires. You would still want to get the connectors off a donor because Toyota only sells empty connector housings and repair wires with the pins on the end and that gets expensive.

What doesn't look good? I understand I'm gonna have to get the connectors off a donor and get a new split plastic loom, but what I don't understand is how am I going to add these connections to my existing harness, if possible? Is it like the kindergarten drawing I made a few posts back? haha sorry for making you work, but it really does help me out a lot so I can get to work :biggrin2:

As others have already said you are going to have to find a donor vehicle to do this properly. Same year and same engine as yours.

Yes, I know.. I'm going to about 3 different junk yards in the next 2 weeks to start my search. Wish me luck! :boink:

 

[TheDurk]

What doesn't look good? I understand I'm gonna have to get the connectors off a donor and get a new split plastic loom, but what I don't understand is how am I going to add these connections to my existing harness, if possible? Is it like the kindergarten drawing I made a few posts back? haha sorry for making you work, but it really does help me out a lot so I can get to work :biggrin2:



Yes, I know.. I'm going to about 3 different junk yards in the next 2 weeks to start my search. Wish me luck! :boink:

Well, you won't add to your harness what isn't there. You would just run new wiring, borrowing what you can from a donor truck.

I may have been wrong. Your rig might have the connection for the 4x4 relay installed. Look in the right hand kick panel for an unused, white rectangular plug, two rows of three pins, with one empty. That would be a very good sign.

We pretty much have to go component by component, wire by wire, and figure out the easiest solution. If wires are there, you use them. If not, you run new ones. Takes time, organization and patience, but totally doable. But we need the pieces from a donor.

 

[TheManOutside]

I may have been wrong. Your rig might have the connection for the 4x4 relay installed. Look in the right hand kick panel for an unused, white rectangular plug, two rows of three pins, with one empty. That would be a very good sign

I'm not entirely sure what you mean by "right hand kick panel", so I just took both the driver side and passenger side ones off. I didn't see anything unplugged (that I know of) however, I did find some very strange things on the driver side...

First of all is this switch (I've noticed it before, never really worried about it) :

What does it do?? I tried switching it with the engine on and off and saw no lights, sounds, or anything.

Here's the kick panel off :

As you can see, wires everywhere.. The only thing I really noticed unplugged were the red, blue, and black wires as seen in the photo. Could that be anything? (Seems way to small to be 4wd related). My open door light is constantly on, could that be why?

Here's looking straight up at the wires (the black and white ones going toward the camera lead to the mysterious switch) :

What is that giant black square thing (middle right, says KARR on it)? The plug seems to be half in, but it wouldn't budge when I tried to push it... Sadly, I don't think I have any unplugged wires :cry2: However, if you look right underneath that black box thing there is a white plug with two "tabs" on it that seem to be covered by some plastic thing... there are two : one has a black plastic thing the other has an orange one (it can just barely be seen behind the switch wire). Is this anything?

Here's another angle of the wires :

Here's the passanger side kick panel off :

I didn't see anything strange here... However, when looking straight up from the floor of where the kick panel goes, I could see this :

It looks like a cable that could be unplugged and sitting in some plastic holder thing, but I can't tell...

Finally, I decided to look under the hood to see if there might be any plugs or wires just dangling around... Sadly, there weren't any, but I did notice this :

This is where the clutch master would go, and there's a screw sticking out of it...? Don't think that means anything but it sure is weird!

Sorry for the enormous post. I don't see anything down there, is there something I missed?

 

[TheDurk]

No, I don't think you did. I wish I had the '97 EWD.

The one interesting thing is that plug that is bolted on to that holder on the passenger side (aka right side--always described as somebody seated in the driver's seat.) I can't see the wire colors--but it wouldn't matter since they change them every year, it seems. '96,'98, and '99 are all different. But the plug is always the same. Here is what it looks like in '99:

It could maybe the relay plug I am looking for. A peak at the pin end could nail that down. Should have five wires in a 2 rows of three layout.


You definitely have a pile of aftermarket stuff going on on the left (driver's) side--probably alarm system. Not my area of expertise. Hopefully somebody else can help ID that stuff.

 

[TheManOutside]

It could maybe the relay plug I am looking for. A peak at the pin end could nail that down. Should have five wires in a 2 rows of three layout.
You definitely have a pile of aftermarket stuff going on on the left (driver's) side--probably alarm system. Not my area of expertise. Hopefully somebody else can help ID that stuff.

I'll try and check tomorrow of that plug you showed me. Is there something you need me to look up in the EWD? I have one (pretty sure it's for 1997). Also, my truck doesn't have an alarm system so I have no idea what any of that stuff is. It used to have a CD player in the back, but I took it out cause it was huge, ugly, and it didn't work :rofl:

 

[TheDurk]

I'll try and check tomorrow of that plug you showed me. Is there something you need me to look up in the EWD? I have one (pretty sure it's for 1997). Also, my truck doesn't have an alarm system so I have no idea what any of that stuff is. It used to have a CD player in the back, but I took it out cause it was huge, ugly, and it didn't work :rofl:

Sorry, I forgot you said you had the '97 EWD. Is it a book or a download? In 4wd, what are the five wire colors on the 4x4 relay? Then we can compare to the wires leading to that plug. It's plug # A18, if that helps. The pin-out diagram is in there somewhere if you want to see what it looks like.