VSC Disable on Pre 2008 4Runners

[CJ3Flyr]

Originally Posted by Mikestang

Sounds like you have a mistake somewhere if the diff lock light is coming on.

The diff is positively unlocked, I am 100% sure of that. As Andries stated the V6 t-case is a bit different than the V8 t-case due to the 2wd function.

I can lock and unlock the diff while in 4HI (or 4LO) and my switch on. It locks & unlocks ok. When unlocked the diff lock light continues to flash even after the diff unlocks. Back to my original recommendation, don’t mode change with the added VSC-off switch in the on position.

It is not a perfect mod. It beats the heck out what Toyota gave from the factory.

[07 Elephant]

Andries as part of the testing of this mod would you mind starting your truck, turn off the vsc and then turn the truck off - remove the key - and then start it again while the vsc off switch is still engaged? What happens? Any error codes or bad mojo?

Chris you've demonstrated the difference between v6 and v8 already...would you mind doing a similar test too please?

As of now the factory switch will not work without modification...and we're working on that. I'm not spending $60 on it though and will hook up a toggle switch in the mean time. And I won't be able to work on it till the weekend.

[CJ3Flyr]

Originally Posted by 07 Elephant

As of now the factory switch will not work without modification...and we're working on that. I'm not spending $60 on it though and will hook up a toggle switch in the mean time. And I won't be able to work on it till the weekend.

Ok, I tested it in 4HI and 2HI by shutting it off, removing the key and then restarting it. (I consider testing it in 2HI it like lipstick on a pig for now. Why bother? How'd you like that current event reference? )

Regardless of 2wd or 4wd at shutdown the result is the similar. It leaves the VSC light on steady and flashes the amber diff lock light. When tested in 4wd the VSC illuminates steady, the 4wd and Diff Lock light both flash. Once the switch is set to the off (ungrounded position) the lights go out. If I had to guess I'd say a relay held circuit with a momentary switch will be the final answer so that the system can complete it's start-up system check It'll end up being like the side-airbags, resets to the default of 'normal' mode when the vehicle is shutoff and then restarted.

FYI- This guy is selling a switch, cheap. http://www.toyota-4runner.org/showth...threadid=41229

[bulldog]

Originally Posted by CJ3Flyr

I just completed the mod. In 2wd dash lights are on (VSC & Diff lock). I didn't mess around enough to decide if VSC is working, traction control IS working; I'm assuming it has full VSC. It has all the familiar noises and accompanying reduction in power. The system seems to get confused if you attempt to change from 2HI to 4HI with the switch on.

In 4HI it works as advertised You have an unlocked Torsen center diff and no interference from the VSC; the VSC and Diff Lock light are on. You can definately feel/hear ATRAC doing it's thing. The same deal in 4LO... My advice is to not do a mode change with the switch on. I may retract/ammend that as I learn more.

Andries, you saved me thousands! I was having serious 'VSC-off' envy of the 2008 guys, thank-you!

Cool thx for the feedback. I had a feeling that it wont work in 2wd after looking at the wiring diagrams and descriptions again.

I would definitely recommend to turn off the switch if you try to switch between 2H and 4H.

It is very likely that the V6 might report different dash lights than the V8. However just double check everything and also make sure that the switch is off before you switch between 2h and 4H, this might affect what is reported on the IP.

[bulldog]

Originally Posted by 07 Elephant

Andries as part of the testing of this mod would you mind starting your truck, turn off the vsc and then turn the truck off - remove the key - and then start it again while the vsc off switch is still engaged? What happens? Any error codes or bad mojo?

Chris you've demonstrated the difference between v6 and v8 already...would you mind doing a similar test too please?

As of now the factory switch will not work without modification...and we're working on that. I'm not spending $60 on it though and will hook up a toggle switch in the mean time. And I won't be able to work on it till the weekend.

Will look at it sometime this coming weekend.

Seems like it si more successful as a V8 transfer case mod, as I must be honest that I didn't look too closely at the V6 diagrams. Seems like on the V6 the 4WD ECU might have to be modified for it to work best, or a whole bunch of wires will have to be run through a series of relays to work correctly.

[07 Elephant]

Chris thanks for testing it out so quickly and getting back to post it.
We figured if the switch was momentary then the ecu is expecting everything to be set back to base line so to speak or it'll start up w/ errors. A scan guage would tell more about the situation we created by leaving the switch closed.
In the mean time discussion here revolves around a d flip and a 5v tranceiver.

[CJ3Flyr]

Originally Posted by 07 Elephant

Chris thanks for testing it out so quickly and getting back to post it.
We figured if the switch was momentary then the ecu is expecting everything to be set back to base line so to speak or it'll start up w/ errors. A scan guage would tell more about the situation we created by leaving the switch closed.
In the mean time discussion here revolves around a d flip and a 5v tranceiver.

Your quite welcome This is exciting stuff.

What I was getting at with the momentary switch was to use a relay to ground the circuit and use a momentary switch to close the N.O. relay. Wire the relay so that it holds itself closed until + is removed. Obviously, the + aspect of the circuit would only be used for closing/holding the relay closed. My suggestion of a relay and momentary switch is only a way to hack around the system and not ideal. It sounds like you're hunting for the right answer. On behalf of many, thank-you!

I have no intention of doing any diff locking or unlocking and or mode changing with my switch on. I don't want to push my luck, something about mods causing stuff to break and then no warranty...

[Mikestang]

Originally Posted by CJ3Flyr

FYI- This guy is selling a switch, cheap.

Sweet, I sent him an email, hopefully I can score that switch. Looks like a fun project to combine the research/work Andries has done with the 08 wiring diagram and see if there's a simple way to make that switch work, woo!

My wife has always loved driving with me in the snow in the 4R because I can't kick the rear end out and all that fun stuff. She's in for a surprise this winter...

[bulldog]

CJ3flyr,

I looked at the wiring diagrams again for the V6. There are 2 more wires you can try to make it work in 2WD.

The one is the Grey wire (pin18) on the same plug. It is the ADD On indicator wire. It works the same as the center diff wire, and also feeds to the VSC ECU. So it might fool the VSC into thinking you are in 4Wd with the center diff locked (while only in 2WD). It is not invasive and works similar to the center diff sensor wire, so little chance of messing anything up. Well worth a try, and definitely would explore this route for the V6 first.

Second one is to look at the green wire with red stripe on the F9 plug in the 4WD ECU (it is pin 20). Unfortunately this one will require some cutting and rerouting of the stock wiring.

So best to try the grey wire first. If you use a DT (dual throw) switch you can ground both wires with one switch, but they have to be isolated when open (and should definitely be disconnected if you switch from 2H to 4H). So before you throw a switch on it make maybe just tap the wire and ground to see how it behaves. Difficult for me as I don't have a V6 to play with.

[CJ3Flyr]

Originally Posted by bulldog

CJ3flyr,

I looked at the wiring diagrams again for the V6. There are 2 more wires you can try to make it work in 2WD.

Thank-you! I will try. I am leaving today on a road trip. I won't be back to play with it for 3 weeks or so

This is my 1st big trip in my T4R. Up to Atlanta then CT then ME and home. That'll be a few miles. If I get any cool pics I'll put them in the appropriate section on the forum.

I know others are waiting on my results. If I get a chance at Dad's house I'll try.

[AlexJet]

Originally Posted by bulldog

CJ3flyr,

I looked at the wiring diagrams again for the V6. There are 2 more wires you can try to make it work in 2WD.

The one is the Grey wire (pin18) on the same plug. It is the ADD On indicator wire. It works the same as the center diff wire, and also feeds to the VSC ECU. So it might fool the VSC into thinking you are in 4Wd with the center diff locked (while only in 2WD). It is not invasive and works similar to the center diff sensor wire, so little chance of messing anything up. Well worth a try, and definitely would explore this route for the V6 first.

Second one is to look at the green wire with red stripe on the F9 plug in the 4WD ECU (it is pin 20). Unfortunately this one will require some cutting and rerouting of the stock wiring.

So best to try the grey wire first. If you use a DT (dual throw) switch you can ground both wires with one switch, but they have to be isolated when open (and should definitely be disconnected if you switch from 2H to 4H). So before you throw a switch on it make maybe just tap the wire and ground to see how it behaves. Difficult for me as I don't have a V6 to play with.

Nice info. Definetly something to think about. If I have a time this upcoming weekend, I might give it a try.
So you suggesting to work on grey wire at the same plug first, not touching the original (1st post) red/blue wire on V6; and then if not worked out try your original red/blue wire mod. Did I get you right? Just want to make sure.

[07 Elephant]

I wasn't able to do this mod over the weekend. Maybe next...

[bulldog]

Originally Posted by AlexJet

Nice info. Definetly something to think about. If I have a time this upcoming weekend, I might give it a try.
So you suggesting to work on grey wire at the same plug first, not touching the original (1st post) red/blue wire on V6; and then if not worked out try your original red/blue wire mod. Did I get you right? Just want to make sure.

Do the red/blue wire first. See what it does. Then do the grey wire as well, and see what it does.

What I was referring to was using a dual pole switch, so you can ground both wires with a single switch. DO not however have the 2 wires connected to each other, just use a single switch to ground them at the same time. This will hopefully fool the VSC ECU to think the V6 is in 4wd with the center diff locked, even when you are only in 2WD, causing VSC to be turned off.

If you only care about turning VSC off in 4WD don't even bother with the grey wire.



NB: Turn off the switch before you change any state in the transfer case (diff lock on, 2wd-4wd, etc).

[AlexJet]

Originally Posted by bulldog

Do the red/blue wire first. See what it does. Then do the grey wire as well, and see what it does.

What I was referring to was using a dual pole switch, so you can ground both wires with a single switch. DO not however have the 2 wires connected to each other, just use a single switch to ground them at the same time. This will hopefully fool the VSC ECU to think the V6 is in 4wd with the center diff locked, even when you are only in 2WD, causing VSC to be turned off.

If you only care about turning VSC off in 4WD don't even bother with the grey wire.

NB: Turn off the switch before you change any state in the transfer case (diff lock on, 2wd-4wd, etc).

Thank you Andries. That is exactly what I need to hear: red/blue then grey. Thank you again.
I'd like to have VSC disable in 2wd as well.
Of course I'm not intend to switch any mods or shut the truck down before turning everything back to "Normal" position.

[Mikestang]

Can anyone point me to a pin-out of the TRAC Off Switch (switch T7, part no. 90980-10933)? I've gone through the entire wiring diagram book and all I can find is a picture of the switch with its pins labeled 1-6, but no notations as too what the 6 pins each connect to.



Trying to see if I can make this switch functional, or if nothing else, use it to trigger the ground splice that Andries has done.

[CJ3Flyr]

Originally Posted by bulldog

What I was referring to was using a dual pole switch, so you can ground both wires with a single switch. DO not however have the 2 wires connected to each other, just use a single switch to ground them at the same time. This will hopefully fool the VSC ECU to think the V6 is in 4wd with the center diff locked, even when you are only in 2WD, causing VSC to be turned off.

In the interest of being lazy I might try it with the switch & wiring that I already have with the addition of a diode to prevent a connection of the red/blue and grey wire when un-grounded. If I do it this way it's quick, easy and all done under the glovebox.

Does that sound reasonable? Thanks.

[bulldog]

Originally Posted by Mikestang

Can anyone point me to a pin-out of the TRAC Off Switch (switch T7, part no. 90980-10933)? I've gone through the entire wiring diagram book and all I can find is a picture of the switch with its pins labeled 1-6, but no notations as too what the 6 pins each connect to.



Trying to see if I can make this switch functional, or if nothing else, use it to trigger the ground splice that Andries has done.

Normally the wiring diagram will include the pins of the switch or module it connects to. You can also look at the repair and diagnostic manuals for more information in terms of pins of modules/switches.

Originally Posted by CJ3Flyr

In the interest of being lazy I might try it with the switch & wiring that I already have with the addition of a diode to prevent a connection of the red/blue and grey wire when un-grounded. If I do it this way it's quick, easy and all done under the glovebox.

Does that sound reasonable? Thanks.

Correct use of diodes should not be an issue. Just using one diode will cause one ground condition to trigger the other, pending where you place the diode. You have to put one in each wire going to the switch.

If you draw a diagram it should become clear.

[bulldog]

Just some feedback on this mod.

I was asked to see what happens if I leave the switch on and turn of the ignition. Basically the 4WD ECU gets confused and the diff lock light flashes, if I leave the switch on and turn the ignition off and on again.

If the ignition is already on and I flip the switch on, only the VSC off light comes on and the center diff lock light stays off.


So I would say the mod is intended to be used only with the ignition on, and not when you turn it off or change state (lock diff or 4H-4Lo, etc).

[CJ3Flyr]

Originally Posted by bulldog

CJ3flyr,

I looked at the wiring diagrams again for the V6. There are 2 more wires you can try to make it work in 2WD.

The one is the Grey wire (pin18) on the same plug. It is the ADD On indicator wire. It works the same as the center diff wire, and also feeds to the VSC ECU. So it might fool the VSC into thinking you are in 4Wd with the center diff locked (while only in 2WD). It is not invasive and works similar to the center diff sensor wire, so little chance of messing anything up. Well worth a try, and definitely would explore this route for the V6 first.

Second one is to look at the green wire with red stripe on the F9 plug in the 4WD ECU (it is pin 20). Unfortunately this one will require some cutting and rerouting of the stock wiring.

So best to try the grey wire first. If you use a DT (dual throw) switch you can ground both wires with one switch, but they have to be isolated when open (and should definitely be disconnected if you switch from 2H to 4H). So before you throw a switch on it make maybe just tap the wire and ground to see how it behaves. Difficult for me as I don't have a V6 to play with.

Ok, I just tried it. There's no difference in indications or behaviour with the grey wire grounded vs ungrounded and my switch on. The green/red wire causes the center diff lock light to illuminate but no changes in behaviour. Keep in mind it was illuminating anyways when my switch is positioned to 'on'.

Bottom line is you have slightly goofy indications but a great mod for 4wd open diff operations and still no 2wd donuts

Andries, again, thank-you!

[bulldog]

I tested the mod on the V8 on the dunes at Pismo this weekend. The throttle doesn't back down with the mod, even while doing donuts. However I was still able to hear traction control kick in at times, couldn't feel it form the cabin though.

It felt like I was able to do donuts a bit better with the center diff open than closed No bogging down as with the VSC on.

Didn't have the oportunity to do fast enough high speed runs with turns to see how it behaves.

I think the next real tests will be a snow run and a high speed desert run, where this mod will probably be the most useful