How To Trouble Shoot 4x4 Actuator

The pic shows the inside of my TC actuator, looks like a bunch of corrosion on the one silver band on the inside of the black plastic part. Could this be why my 4x4 is not communicating properly and not telling the front ADD to engage.

Also I have removed all the yellow grease

 

Put some dielectric grease in there when you get that cleaned up. Did the dealership find that or you?

 

I found it yesterday and took off the plug on the front ADD and found the plastic surround that protects the terminals was snapped off, so I will be making a call to Toyota to say I better get a new $600 ADD. And yes I did put some dielectric grease on it and still did not fix it. Anyone know the correct procedure on how to reinstall the TC ADD onto the shift rod ??

 

Didnt you just replace ADD on the front? So you have problem with transfer case too ?
PS take a look at your PM

 

Looks rubbed off to me

 

I have the same problem as Bhwang. solder the corroded part and sanded it to a nice smooth finish. still having the 4x4 Lo light keeps blinking. it is in 2wd. could it be a sensor problem? (all ADD where tested and worked)

 

If you have blinking light despite being in 2wd, Check that two switches on Transfer case.
Lights on dashboard are hooked to those switches... (aka sensors) its actually a ball on the spring. I would remove each and see if its in stuck.

 

That is a good idea to try and solder it, I may try that next, I have taken the whole TC Actuator off from the shift rod and it was very hard to move the shift rail back and forth from 2hi to 4lo so I am guessing it is a bent shift rod possibly, but have it back in 2hi now with the lights blinking at me just like you

Yes brand new ADD installed by the dealer, last night went to inspect the plug and wiring from the ADD and found that the surronding plactic that holds the plug onto the ADD was broken off (brand new $700 part), phoned the dealer and they are going to replace it asap, but still a pain. As i said above now I am thinking it could be a bent shift rod, any ideas ???

 

yeah no luck i think i am just going to get a manual TC if i can find one. thank still willing to T/S and repair but just nothing seem to work.

 

That's simply not true, they are fed into the 4wd ECU and the ECU used that information in conjunction with the 4wd switch to determine which. Dash lights to illuminate. 99% of the issues are caused by the junk actuator design; looks like something Rube Goldberg would have made all to simply shift a fork 1/2". Those position switches on the tcase are quite reliable, and are used in many applications such as the elocker and transmission. If the light is blinking, best bet is to pull the 4wd fuse and start taking ohm readings to see where your problem lies.

That being said, I have a spare 4wd switch, 4wd ecu, and tacoma transfer case in working order if anybody is interested.

 

so it could possibly be the 4x4 ECU? and if i take any ohms reading's i could be reading through the whole circuit so should i start at the front ADD and work my way back to the ECU or vise versa

 

Just saw this thread while looking for ADD actuator pics.

This tech tip put out by Toyota has been helpfull for me to diag an 06 Tacoma. It shows you a pinout of the 4wd computer and all the values you should see in each of the drive ranges(2WD,4WD,4LO)

https://www.dropbox.com/s/2kkxl5mc1rp3pze/38068.pdf

 

why not just drill through it and put a small screw with washers and a lock nut on it? use some loctite or otherwise on the threads to make sure it never comes apart?

 

Well, after reading up all over the forums, I took the dive and decided to take my actuator off. It really was a pretty easy job, drained the front diff oil, popped it off, and tested it with a lawnmower battery. The first time I applied voltage to pins 1 and 2 it pulled a lot of current, but nothing happened. I took the housing off and powered the motor directly, and it turned really slowly. After fiddling with it, the motor started working normal again. I don't think it was the contacts, but I soldered them anyway. Maybe the motor got hung up and taking it apart cleared some trash out? Not sure, but I put everything back on and now my 4WD works again .

The way everything is positioned would make that kinda hard, it's gonna be WAY easier to grab and iron and flow a little solder onto it.

 

Guys, what sort of grease is used inside the actuator? Saw a number of greasy photos...
EDIT: Bought CRC di-electric grease. Sounded like it's what was needed.

 

This^

I had a 2 year long lemon law case with Toyota over this, and then I fixed it in a day.

That's what I used.

 

What if you pre drill a hole in each terminal and install a copper bolt and nut ?

 

You could do it on the right one, the left one looked like it'd be a little tricky to get to with a drill. Maybe you could take the whole motor out and try. Gonna need some tiny screws and drill bits.

 

Hey guys, I'm having 4wd issues.

My truck got stuck in 4hi last week so I pulled the front driveshaft to drive it home. No matter where I put the selector switch the output shaft of the transfer case would still spin. The 4wd light blinks constantly regardless of where the switch is.

Today I manually switched the truck to 2wd and the 4wd light is still blinking. I took the transfer case actuator and looked at it and it's very clean, no corrosion or anything odd looking. Is it possible the actuator itself is shot?

I haven't looked at the front diff actuator yet because I figured if it was the issue I would have been able to shift into 4lo when I was stuck in 4hi or even shift into 2wd.

Any thoughts are greatly appreciated! Thanks!

 

Anyone know which pins are power and ground on the transfer case actuator?

1 and 2 like the ADD?