Need help with 2002 4wd A.D.D system.

[calimobber]

Hey all,

Looking for some help from the forums with my 2002 4wd A.D.D system. . I went through water and some got into the A.D.D. I pulled the front diff and removed the A.D.D and bought a used one on eBay and I can't get it to actuate.

I have read into the toyota manual and tried checking the wire pins for ohms and Its not showing up like I would expect. pins 4-6 and 4-5 both don't show anything with the button clicked.

So I'm getting stumped. I wonder if the water shorted something or not. seems like if the eco was shorted other stuff would not work, but it all works fine.

Has anyone used 12v and just connected the unit off the car to see fig it moves right?

Thanks

 

[jgue467]

Have you checked the FSM, it shows 9 possible issues related to "can't shift from 2 to 4wd", one of which is the ADD. If the old and 'new' ADD won't engage perhaps it's another one of the other 8 items causing the issue?

 

[calimobber]

Have you checked the FSM, it shows 9 possible issues related to "can't shift from 2 to 4wd", one of which is the ADD. If the old and 'new' ADD won't engage perhaps it's another one of the other 8 items causing the issue?

So I have made progress. I think I was looking at the 4x4 center lock a.d.d section. I found how and where to apply power to the actuator and it moves perfectly and shows the right continuity.

I kinda confused on one thing. Does the 2002 4runner have a relay or does it get its signal directly from the 4x4 ecu?

Looking at the picture it shows w/2-4 selector and w/o 2-4 selector.

 

[calimobber]

update. The manual says to check the 4wd switch on the shifter. pushing it in should get continuity and out should not.. Ive tested a few times and I don't get any beeps on the meter just some ohms readings.


Im thinking maybe the switch busted. Ill keep you updated.

 

[HiluxSurf SSR-G]

there's a thread over at YT that may help you. the thread title says 1999 but there are several solutions to 2001-2002 issues as well

 

[calimobber]

there's a thread over at YT that may help you. the thread title says 1999 but there are several solutions to 2001-2002 issues as well

Humm I think thats the one I have been reading about. I guess today ill dive in and look for a relay in that spot just to see if its there and if so, test it. That was for a 99 manual so I think it has a different setup.

:thanks:

 

[HiluxSurf SSR-G]

iirc, in the last few pages of that thread, the discussion was more on the 2001-2002 4WD/AWD issues

Humm I think thats the one I have been reading about. I guess today ill dive in and look for a relay in that spot just to see if its there and if so, test it. That was for a 99 manual so I think it has a different setup.

:thanks:

 

[calimobber]

***Update***


So to keep everyone updated. I reinstalled everything and applied 12v to force the A.D.D into AWD....or so I thought. When I put it all back together I realized the center transfer case was locked in 4x4 and would not shift out. So the center lock is locked and now its in 4x4 always.

So either the center lock is messed up also from the water or the system is just out of wack. I will try and manually apply power to the actuator and see if i can unlock it. I read on the 99 4runner thread on yota(suggested earlier) that some times the system can just get out of sync and won't work. So you have to manually unlock it all and start over.


If thats not the fix, it sounds like that actuator is very expensive and is hard to fix. So I will just buy a used transfer case, since they only seem to cost like $250 total. Ill keep everyone updated.