06 Tacoma 4x4 no power to transfer case or diff actuators.

New to this group. I've got no power to actuators at all. Fuse is good and light blinks on dash regardless of the switch position. With all connections unplugged I can not get any power to any terminal on any connector under the truck. Suggestions please.

 

I’d start here.
Read everything you can in these 2 links.
However, I’ve linked you to the most helpful part.

https://www.tacomaworld.com/threads/how-to-trouble-shoot-4x4-actuator.263525/page-7#post-8538436

https://www.tacomaworld.com/threads/4x4-problem-i-cant-resolve.575092/#post-19056025

Oh, Welcome to TW

 

check the 20 amp 4wd fuse under in the coin slot area drivers side

 

Crawled under again and t/c actuator is not working. With ign switch on and selector switch in 4hi the front shaft still spins freely but I get a steady chirp chirp sound from DIFF ACTUATOR.

 

Sounds like your transfer case actuator is in need of some repair.

 

Can I expect any surprises when removing the t/c actuator? I've never been into one before.

 

Setting up the timing on the gears can be challenging but it’s sort of like taking apart a drum brake. Take lots of pics

 

I would take the cover off (3 - 10mm head bolts) and check the contacts inside, they may just be corroded.
This isn't the best video but it shows the cover removal: https://youtu.be/n3NN5wYbDqA

Note I would not take off the actual motor just yet as it might be difficult to reassemble.

 

I'll take everybody's advice and take a few pictures. I've only had this truck about 8 months and it has 160k miles on it. The add had red silicone on it as well as the t/c but both actuators look very clean to have that many miles on them. Thanks for the info, I'll post my findings.

 

rktman, I took your advice and removed the cover. It was dry as a bone with no corrosion. I smoke tested the motor and it runs quiet both directions. As I stated in my 1st post the 20amp fuse is good and has power to it but nothing at the connector. I'm going to put the cover back on and use a separate battery to see if I can make the motor shift positions. When changing from 2 to 4 hi does the rotary switch supply power momentarily or continuous? I spent 41 yrs of my life in the auto parts business and have been retired for years, I got out before the electronics took over so much. One last question for now, how do I post pictures on here?

 

switch will have continuous power. Likely around 10 volts there’s a diode when 4 hi is selected. Measure from pin 5 to pin 4 of the switch. To post pics hit “upload a file”, select the pic, then once it’s at the bottom of the screen attached hit full image.

 

Be sure to use some dielectric grease on the contact cover reinstall..
Also, you might check your position indicator switches for continuity when depressed (the 2 switches on top with the 27mm (or 1 1/16) heads)

 

I put it together and used a small battery to activate it and it will shift to 4hi and 4lo and reverse the wires and back to 4hi and 2wd but rotary switch will not do anything. How much of the dash do I have to tear out to get to that switch? I think that's my next move. I plugged the connector back in while it was in 4lo and it would not engage the front diff. I'm thinking the reason for that is no power to t/c actuator. I would love to have a wiring schematic on the 4x4 wiring on this thing. Thanks to everyone for the responses. I'll keep after it

 

just pry it out by the vent, comes right out. None of the dash has to come apart.

 

See attached, hope this helps. Good luck.

 

At one time, I think there was a picture of the contact strips in the inside of the actuator.
Some one had “mapped” out the areas as to what spots were what in relation to 2Hi, 4Hi, and 4Lo.
I can’t seem to find the picture now.

Maybe some one has it saved and can help you out?

 

I pulled the switch, took it apart cleaned it and used diaelectric compound and after reassembly checked it with a meter. Contact is good and diodes are ok. The harness that plugs into it has no power to it with ign on. Now what? There most likely is a relay under the hood for it but I have no idea which one.

 

What switch are you talking about?
The actual switch on the dash that turn to engage 4WD?
If so, there is no relay. It goes to the 4WD ECU.
In the T-TT-0052-10.pdf file that 6Gear provided above, you will find a diagnostic chart.
It shows you what reading you should find in each 4WD mode.

 

I have been studying all the info that is being posted and I'm about to get it thru my thick head how this operates. Thanks to everyone for the help. If the storms don't get me tonight I will try to check all of it tomorrow. Glad I've got a nice warm shop to work in. I'll post what I can tomorrow.

 

Awesome.
This system is not a “simple” as the 1st Gen trucks.
Who would have thought an electric motor would be “better” than a physical shift lever?
Not me.

Keel is update