Over-ride / manually operate 4wd actuator?

How can this be done on the trail in case of a failure of the actuator?

 

Simply, you can't, the actuator holds the selector in place, you would need a locking device to hold it. A vice grip might work in a pinch, but if the limit switch for 4x4 doesn't work it won't actuate the front diff.

The front diff has a sliding sleeve that also can't be overridden because it needs to be held in place at a specific spot.

If you get super serious you can put a FJ cruiser transfer case in with actual levers, and there's ways to delete the ADD in the front.

The front differential disconnect (ADD) is the weak point on these trucks. The real secret is to carry a spare ADD actuator.

 

Well, that’s a bummer.

Contemplating the fj case, but it’ll be way down the line.

 

@Bishop84 do you know how much a ADD runs? New or used?

 

I've had customers supply them from online for around 200$, I think Toyota's price is 600$ haha.

 

Ouch! $600 is nuts

 

Might you have a Toyota part number?

 

You can electrically override both actuators. Pull actuator connector on each actuator and apply 6v-12v to the appropriate pins. Only works if motor is still connected electrically and not jammed. This will 'override' feedback position switch failures.

 

Awesome thanks. Do you have a diagram showing which pins? Or what color the appropriate wires are? No worries if not.

If they’re jammed, any steps to try to free them up?

 

I have more written up some more previously (that I can see if i can find tonight or tomorrow.) I know on front ADD its pin 1 and 2 on the ADD connector, heavier gauge red and blue wires.
See 2 wheel lo schematic in my thread in sig.

From playing in general to free up an issue,( with no actual failure modes), on the front ADD.. I jack 1 front wheel and spin free tire while trying to get ADD to engage.

If this overall is a significant fear, it would well be worth it for you to make a breakout box. Spend about $20 on connectors, some wire, and a little box with a few switches (some LEDs if you want to get fancy, but probably not worth it). Let you manually force position of either actuator (if the motors are still viable) regardless of the ECU being pissed.

If you want some help with this idea, I can give you some info and we can try to put something elegant. (If you are really interested in building one). I have thought about making one of these, as I found I could inadvertently put the front ADD into invalid positions while doing 2wheel low failure mode testing, 4wd mode change were then locked out.

To get 4wd back, I had to manually run the motor by putting a few volts on it to get back into a valid actuator position. I just did it with a few pieces of wire and a flashlight 6v battery pack, but a premade harness to do it would be sweet...

This making sense? Sorry, kinda jibberishy.

 

ADD





Transfer Case



For toyota parts here is approximately what I come up with (cheaper may be available overseas, etc.)
ADD Side
90980-11858 ~$12.18
2 *

$10 82998-12440 Genuine Toyota Parts - Terminal, Repair W/W (82998-12440)

82998-12440 ~2*$6.57

Transfer Side
90980-11151 ~$9.85
2 * 82998-12440 ~2*$6.57

~$48.31 total for toyota brand connectors or pins


(plus some long wiring, a few dpdt switches, and a power source, or 12v battery connection.)