4wd System Operation & Help Thread

I'm not sure who actually makes the actuator for Toyota but the aftermarket ones are hit or miss like most aftermarket stuff is these days.

 

I need your help, i cant get my actuator to work. These were my backprobe readings

If i cycle key while in 4hi or 4lo the readings change

 

Where are you taking your ground readings at? A bolt under the dash?
Or back probing off a connector?

Looks like you have voltage bleed over somewhere.

What happens if you unplug the the connector at the actuator? Do the voltages go to 12v?

 

I'll have to sit down and study this more later but at a glance those voltages are really low, what is your battery voltage?

 

Yes bolt under the dash. V read the same with connector off or on

 

Battery is 12.4

 

Check across F12 (A) Pin 5 (Violet) and Pin 6 (White/Black) and see what your input voltage is to the 4wd ECU.

 

I was just trying to find the PIN numbers.
lol. The schematic is blurry if you blow it up. Maybe we need to add a .pdf of the wiring diagram to the first post.

I’m on my phone and don’t have access to “other” diagrams.

 

Yea I need to update that.

It would be IG and GND on the connector images.

 

Currently going back through the thread to locate these, my knowledge on this stuff isn't the best lol

nvm i got it, so jump those 2?

 

Yeah. I was looking for the PIN number. Just to make it easier for OP. Went to zoom in and blurry.

We can add a .pdf later. No big deal.

 

At the 4WD ECU in the dash.

 

Pin 6 0v pin 5 12.0

 

Just to add, sometimes if i switch the knob, cycle key off/on. i can get the actuator to move. It’ll stay in 2hi. If i walk away come back to it, turn key on light will flash. Knob wont do anything. Turn knob to 4hi cycle key off/on i can hear actuator

 

Well that tells us we have the correct voltage going in, now we have to figure out why it’s not right coming out.

Dm93 can offer a better way to test the out. But we need to eliminate the wiring to the actuators first.

Something strange is causing the 4wd ECU to read 8v out. And the ECU rarely goes bad. But it’s possible. We need to eliminate all possibilities.

 

Ok so i went ahead and backprobed a few with the truck running, and some are reading 10v and some 9v pin 5 on f12 was at 13ish

 

Check the voltages on the grounds (White/Black) wires at Connector PA on the passenger side Junction Box behind the glovebox and make sure those are good.

 

Unless i am doing it wrong but those all read 0

is there any place i can get power in cab?

 

Ok. Somehow you have a 6v difference in all the readings. Battery is 12v minus 6v is 8v. AKA your readings.

Then you get 6v at the 0v readings.

The only one you have that reads 0v is the ADD Actuator. Have you unplugged it and see what the readings are then. That’s the one on the front axle.

A voltage meter reads voltage difference between the 2 probes. Not actual voltage on a single wire. For instance, if you have 6v on one wire and 2v on the other. The meter will read 4v.



For curiosity sake. Find a new place to use as your ground point. Then place the red lead on what ever you were using as your old ground point. We need to figure out this voltage issue.

For sure unplug that ADD and try again.

 

Ok so did the new ground to existing ground and nothing

disconnected the add and now im getting 4v on that one in 2hi 4hi and 4lo