Defeat toyota locking RR Diff. constraints

[translunar]

I just bought a 2013 FJ and was not told that all the fine off road 4x4 controls can only be used in low range 4x4. I did read an article a LONG time ago, where a guy cut and grounded a wire to the little ECU for the toyota electronic locking rear diff. Does anyone know how to do this to a new FJ ? send me a private email.
Thanks...... Oh, I love my new rig, all white, standard steel wheels, trailer hitch, roof rack, rock crawler dial.

 

[rusty_tlc]

I would suggest you are better off letting the ATRAC system do it's thing in Hi Range.

I cannot think of an occasion where locking the rear diff would be an advantage in Hi.

 

[translunar]

ATRAC according to the manual can only be used in 4 low.

 

[ironhippy]

Any popular FJ cruiser forum would have detailed instructions on which wire to ground.

I've never needed my front or rear diff locked in anything other than low range.

 

[rusty_tlc]

ATRAC according to the manual can only be used in 4 low.

I did not know that. Seems like ATRAC would have advantages in high range to me, icy roads deep sand etc. Enabling ATRAC in Hi would appear on the surface to be a better mod than enabling the rear locker in Hi range.

 

[Fast Eddy]

I would guess that Toyota engineers are worried about how ATRAC would affect vehicle stability at higher speeds. I would have to agree with them that hitting the brake on one side at any road speed would be a "bad idea".

 

[rusty_tlc]

I assume all modern vehicles have a speed sensor input to the ECU. It seems like it would be a trivial programing task to enable ATRAC only at low speeds. Not for the DIY'er but as a design feature by Toyota.

 

[SIZZLE]

Check out an FJ forum or Tacomaworld. They got hacks for this.

 

[IBCRUSN]

Here's a link to a thread to address what you're looking for.

http://www.fjcruiserforums.com/foru...ion-aids/34823-rear-diff-lok-demand-hack.html

Also you might consider the ATRAC hack as well because it won't work if you two-foot drive (i.e. modulate the brake and gas at the same time). You'll want to modify the brake input to the ATRAC ECU.