Pre-runner conversion ADD wiring idea

I am looking for help in determining if the proposed ADD wiring solution would accomplish my goal of allowing my converted 4WD to work like a factory installed option. I consider this wiring project to be more of a retrofit than a conversion since the two models do not feature the same wiring schematics.

Disclaimer, I am not an electrical minded person. I am a physical therapist that sidelines as a carpenter. I did my best to interpret how these 2 systems work and took a stab at merging the 2 wiring diagrams by utilizing the ADD relay in the 1999 tacoma to power the VSV solenoids. I have attempted to color match the wires and describe what I believe to be the accurate location of each needed splice point. These ideas are detailed in the spreadsheet below.

Below I have attached an idea for wiring in the vacuum actuated ADD system into a truck that wasn't pre-wired for the VSV solenoids. I believe that my 2001, if it had been born 4wd, would have been wired for an electrical ADD system as detailed in the wiring diagram below. The parts truck that I am pulling all of my 4WD components is a 1999 with the vacuum ADD. I have included a wiring diagram for that truck as well. I believe that my wiring proposal would avoid the need for the ADD system to communicate with the transmission control relay in my truck(if I have one) that seems to be deeply connected with the electronic ADD actuator.

I am looking for help from a more experienced electrical mind to determine whether or not this idea would work. While I am concerned with functionality in this project, my main concern is safety. I do not want to tear up my 4WD parts or burn up half of my electrical system based on my own electrical retrofit efforts.

Note, in the attached wiring diagrams I have used whiteout to remove the wiring that wasn't pertinent to my vehicles. This includes wiring for the ABS system, 3RZ motor, manual transmission, etc.

My truck: 2001 Double cab w/automatic transmission
Donor truck: 1999 Ext cab w/automatic transmission, j-shift, Vacuum ADD system

 

I've done it a few times . Very simple to do. I'll look at your disgrams when i get to my pc.

 

I almost PM'd you about this before posting the thread. Haha, none of this stuff is "very simple" in my world. Electricity is a pretty foreign field of study for me. I did have some physics classes that concentrated on electrical circuits, but like most college courses they never teach you anything relevant to the real world.

 

I've always done it with just a standard universal 12v relay and just used this part. It doesn't need to be tied into the ECM. The 2 red wires are tied together

 

@Empty_Lord might have some input on this.

Not sure on differences between 01 and 02, but we've been discussing what (on the wiring side) would be needed for ADD on the 02 PreRunner.

 

check your wiring in the truck. For the 02 we have it appears to be wired for a j shift 4wd setup inside the cab. so a 4x4 ECU and adding some wires outside should make it all work factory like with a Transmission relay. but you'll have to pull kick panels and check if the 01 is like the 02

 

i just reread and saw it was a VSV based ADD, honestly i would just swap to the Electronic ADD and you can wire it to be just like a factory 01 4x4 setup

 

I added ADD to an original 4 cylinder automatic with a j shift. I converted the truck from auto to manual first. I kept the manual locking hubs for another purpose. I did a similar job as mechanicjon, but I used a stock relay. I tied into power from a junction block and activated the relay using the ground tied to the 4wd light. Just pull back on the j shift the relay is grounded and the light comes on. Post #117 is where I began at https://www.tacomaworld.com/threads/this-99-taco-again.521581/page-6

 

I considered doing that but it looks like those electric actuators are fairly expensive. I may call a couple local places tomorrow to see if I can get one for a reasonable price.

 

That makes sense. I honestly am getting better at comprehending some of this wiring. What you posted isn't a far cry from what my first post was about. For someone who doesn't know what they're doing, I seem to have been on the right track.

It'll be a few days before I get to test any of this wiring. I still have to pull the rear axle, transfer case, and transmission from my donor vehicle and pile those parts next to my truck. Then, I get to install my trans and rear axle into the donor truck. Joy. Anyone want to drive to Arkansas to buy a 4wd converter to prerunner from me lol?

All jokes aside, I will keep you guys updated on the wiring. I have another thread where I was discussing the compatibility of the parts truck with my truck. That thread will likely turn into my main 4wd conversion thread soon.

 

Junkyards should have a fair bit of them. Tundras, sequoias, 4runners and tacos had them.

 

Why are you changing the rear axle? Different gear ratio?

 

I have one on my shelf that I pulled off my truck and the solenoid box that goes in the kick panel. $125 for both shipped. Parts are off my 02, shoot me a PM if you are interested.

 

shit.. if he dont want it.. i might have to grab that Relay/solenoid box from ya if its the one from the passenger side kick panel.

the 02 is getting 4x4 eventually.

 

There's the part number. I also have the elocker box right next to it that I'm no longer using.

 

2.7L?

 

yup, thats the box. i'll check tomorrow to make sure it isnt already there. but pretty sure its not.

the 4x4 computer for the elocker is there in the driver side kick panel already

 

What's the silver box in that pax side kick panel, I thought that was the elocker module?

 

3.4

 

i'd have to look. the 4wd computer is in the driver kick panel. im pretty sure thats what controls the elocker.