before i begin, please forgive me if I am asking something that's already been answered.

I will give a somewhat detailed story so you know where I am at. I bought a 99 4runner and made sure to check the 4wd first before buying. I dropped it into 4Lo and felt it shift, drove it a few feet. Back into 2wd and was happy with it. On my first outing on some dirt roads, found out real fast the 4wd wasnt actually engaging. I started digging around and realized that someone had cut the wiring to the ADD actuator. So I did the right thing and permanently engaged the front diff thinking that was the problem. Well it was, kind of. The transfercase still wouldn't engage. So I climbed under and saw that I had no wiring going to any position switches or the t-case actuator. I realized that someone had at some point put in a new wire harness but it was for a 2wd 4runner. I bought the harness I need, installed it, but dont seem to have anything to plug the t-case actuator into.

This set up is certainly not factory. I've bypassed the ADD system entirey (not concerned with that) but I have no idea what or where my t-case actuator plugs into)

Does anyone have info on this? Can anyone supply me with a few photos of what their actuators are plugged into? Or the wiring? I even downloaded the full wiring diagram and cant find anything regarding the actuator. I am lost. Please help

 

Ummmmmm....

If you want 4WD to function at all, the ADD system has to be active. After all, the T Case position doesn't matter in the least, if the front wheels are not connected together through the front diff. If they aren't connected, the front drive shaft can turn all it wants, but it won't apply any power to the front wheels.

If I misunderstand you, I apologize. Perhaps you mean you have the ADD permanently active, so the front wheels ARE connected together? If so, I apologize. If that's the case, yes, 4WD will function properly. The downside is that you're wasting a lot of fuel mileage. That's what the ADD is for, to save mileage, as well as wear-n-tear on the front equipment. The differential, drive shaft, axles and so on. That stuff isn't as robust as the rear equipment, and will wear out a lot faster if the ADD is always engaged.

Either way, it's not right, and should be returned to factory, if at all possible.

Anywho, attached please find the PDF from the FSM about the 4WD system. Not including the ADD, but it includes the actuator, and much good information after the schematics of what plugs into what, and where. I hope it's some small help.

Good fortune.
Pat☺

Edit: I apologise. The schematics and descriptions DO include the ADD system. If you need the component location or wiring harness routing and plug locations, I have those PDF's as well. Let me know.
Pat☺

 

I suppose I didn't write it correctly but yea I have it so the ADD is permanently connected. I am not concerned with the wear and/or fuel mileage as i have a daily. This is more of a project. Thank you for the PDF. I am going to take a look at that and see if it'll help me. I notiecd this morning with more crawling around under the rig that the female half of the plug for the actuator is MIA (no cut wires either so thats confusing) and I am also missing the plug for the position switch thats on the actuator. This mystery is getting deeper.