VSC Off, ATRAC On Mod complete!

[chaz]

jbtaco, any update yet on whether the oem vsc off switch worked on ur v8 without cutting & splicing (kliv stated it may work on v8)

 

[jbtaco2002]

jbtaco, any update yet on whether the oem vsc off switch worked on ur v8 without cutting & splicing (kliv stated it may work on v8)

The OEM switch worked fine, but i did have to cut the wire and splice it in by the Skid control ECU.

also, dash indications aren't 100% accurate, when i press my VSC switch, both the VSC off and center diff lock dash lights illuminate. It's manageable because i know that the center diff isn't locked and the only way i've found that makes the dash lights more accurate is to press the center diff lock button, and then turn it off. you hear it engage then disengage but now the center diff light is flashing on the dash.

so in the end it's not perfect, but it's nice to be able to disable VSC whenever i want, then re-enable it on the fly. easy mod

 

[chaz]

thanks for update, any pics of splice in engine bay?

 

[Snesley Wipes]

Wonder if anyone found out if just putting a 08 ECU in an earlier model would just be plug-n-play and solve the light problem. I always ask at the dealer but every tech gives conflicting answers.

 

[Coldnapalm]

This was great. After waffling for months on spending the extra money for factory switches, I finally decided to do this. For the record I have a 2005 4WD V8.

A slight variation:

After having the dash apart & running the wire to the 4wd control ECU as shown, I noticed an unused connector (blue) on the left side of the dash where the switches go. I tracked it down in the wiring diagrams & discovered it is the connector for the "Trac Off" switch [which I believe is for 2wd only variants]. Being curious I looked at the diagram further & realized that the red with white wire for Trac Off runs to the skid control ECU. The red with blue wire that we tap at the 4wd ECU for this modification ALSO connects to the skid control ECU. Same wire. Hmmmm...
So, I purchased a used "Trac Off" switch and for ha ha's, I connected it to the empty blue connector & (breath hold...) tried it. Nothing. I confirmed that on my 4wd, the "Trac Off" switch has no effect on the condition of VSC (or any thing else that I could tell). Now on the 2005, the skid control ECU is in the engine bay at the brake fluid reservoir (I think its under the dash on earlier models???). I confirmed that the red & white wire in the connector (at position #43) at the skid control ECU is in fact the same wire at the blue connector behind the dash. The wire I needed to tap (red/blue) was at position #27 of the same connector. I simply cut the red/white wire close to the connector & tapped it into the red/blue wire a couple inches from the connector (I had to remove some of the loom & tape to tap it there). I sealed the connection (heatshrink tubing) and re-taped the harness & replaced the loom.
So now I have a factory looking switch all connected to work the VSC off mod. The ground needed & illumination wires are already in the blue connector so the total installation was VERY easy!

But wait, the "Trac Off" switch is only a momentary switch you say. Well fortunately some one else had shown (I think on this forum - will research it) how to convert a momentary switch into an on/off one. Not that hard. Briefly if you can take apart any on/off switch, you will see that it has a very thin wire across it and a slightly thicker "Z" shaped (kinda "Z" shaped anyway - maybe describing it as two offset bends is better?) that rests on the first wire. Simply duplicate these pieces (I used two thin pins of the same diameter). It is important to DUPLICATE the "Z" shaped pin as closely as possible - a little trial & error. Remove the white plastic piece inside the momentary switch (you will see the on/off switch does not have that piece) & put the switch back together. Voila! An on/off "Trac Off" switch.

Now the purists will say that it's only turning the VSC off & not the traction control off. I know; I would have preferred to use a "VSC off" switch but I know what my switch does if I use it. For the "plug & play" ease of installation this slight discrepancy was worth it to me.

A word of caution if anyone proceeds with this. I originally used copies of the 2003 wiring diagram. For that year, the red/blue wire at the skid control ECU is listed at position #3 & the red/white wire is at #26. The 2006 wiring diagram mirrors what I found on my 2005 (YMMV!). Please confirm what wires you cut / tap beforehand! For mine, on the skid control ECU connector #41 is light green, #42 is RED/WHITE, #43 is also RED/WHITE, and #44 is white/green. With the connector disconnected from the skid control ECU check for continuity between the red/white at #43 & the red/white at the blue connector for the trac off switch (WITHOUT the switch connected to it).

Thanks go out to CJ3Flyr & Andries (at T120) for giving me the courage for this!


In the 1st picture below is the connector for the skid control ECU. To disconnect it, pull the white locking piece forward (about 1/2 way in photo) & pull the connector itself easily toward the fender at the same time.
In the 2nd picture my fingers point to the red/white wire I cut (connect the other end - not seen here - to the red/blue wire) & the red/blue wire to connect/splice/solder it into, the one that runs over the screwdriver in the picture NOT THE BLUE WITH RED AT THE TIP OF THE SCREWDRIVER. The black cover that snaps on (you can see it in the 1st photo) has been removed.
The 3rd shows the switch I used that plugs into the factory harness without modification to the plug or wiring.

So lets me ask this, if i take that red blue wire cut it attach it to another wire run the wire to an off off switch and back into the wire i cut will i have an on off vsc switch so i can floor it in the dirt and make the wheels spin in 2h? [ i did this in my fj worked great seems more complicated in the 4runner?]

 

[alarka]

Bump ,any downsides to this mod yet?..I got a 03' v8 i am gonna use this mod on.

 

[Daron-t4r]

If I were to go to an electronics store and buy a switch, what kind should I look for to do this mod?

 

[SSt4r]

Daron, if all you're looking to do is this mod. with a basic switch, all you need is an on/off switch of your preferred style. I like a factory "look" and did the extra effort just for that. Essentially all mine does is connect that wire to ground when I want turning off VSC.

Coldnapalm, If I understand you correctly, doing what you describe would NOT give you the ability to turn VSC off. In fact I think just the opposite: If you turn the switch off in your settup, I don't think the truck would EVER be able to turn of VSC even when it wanted to (preventing that wire from EVER seeing ground). (just a guess though)

alarka, Haven't seen any down sides yet. Just remember to turn back on when you don't need VSC off. It has saved my ass at least once! That being said it has also put me in danger several times so I really like having the ability to turn it off.

 

[Kliv]

any chance this works with the V8 models as well?

The mod got tested on V8 and it works fine! Special thanks to TRDCal who tested it on his truck.

 

[Daron-t4r]

Ok, doing this mod tomorrow. Does anyone know where I can splice from to get power to my switch? It's got a neat blue led in it that I'd love to light up.

 

[Daron-t4r]

Anyone on the power question? ^

 

[20034RunnerV84x2]

absolute NOOB question coming here...


VSC = Vehicle Safety Control

ATRAC = ?????

I am completely missing the point on this mod. What is the point of disabling VSC and being able to keep ATRAC going with 4WD Hi/Lo and 2WD?

What is the advantage? Sorry, I don't know what all this stuff mean :*(

VSC= vehicle stability control. Lol sorry.

 

[SSt4r]

Daron, You don't want to connect 12vDC (power) to your switch. This mod uses the switch to connect a computer control circuit to ground. Back-feeding 12v to that circuit might be very bad (expensive) for the computer. It would probably also blow the fuse from wherever you got 12vDC from. I don't think you can get the switch you have to light up in this application.

 

[Daron-t4r]

OK, thank you for the input.

 

[TRDCal]

Anyone on the power question? ^

How many contacts on your switch? If the switch and the light have seperate contacts, 2 each then you're good.

You just have to run the ground thru your switch for the mod and run a wire from your 'VSC off' light in the dash to the light in your switch. Then when you activate the mod, the VSC light on your dash comes on and it powers the light in your switch. But you'll want to take some readings with a meter and make sure its not going to fry the light in your switch or be too much of a load and blow the fuse. I don't know...just a thought

 

[Kliv]

Then when you activate the mod, the VSC light on your dash comes on and it powers the light in your switch.

VSC light may come up with locking diff or even with Check Engine... it will lead to misleading button light in the switch. If I were you I would add relay which grounds wire from VSC ECU. Control + to the relay should light the button simultaneously with closing relay. That is safe and will not require messing with VSC light wires. Moreover, you may add fuse to guarantee safety. You may use + from, say, center diff button switch.

 

[TRDCal]

VSC light may come up with locking diff or even with Check Engine...

Oops...I didn't think about that. I guess thats why its always good to get multiple opinions

 

[me_rikey]

Has anyone installed the factory VSC off switch using a relay, while retaining the factory function of the switch -- i.e. that it works similar to the RSCA switch? Press and hold to activate, when you turn the vehicle off and back on, the switch is off.. Hope this makes sense, but curious to see how the relay is installed, because that's how I'd prefer to install it.

 

[WhiteManFlail]

Did someone have a wiring diagram for the '06 V6 4WD? You all have me itching to Mod.

EDIT: Found OEM VSC Switch for '08 T4R at ToyotaPartsZone.com for KLIV's VSC kit. But still looking for Wiring Schematics for my year/model so I know exactly what color wires to touch.

 

[LOSTR4]

Are there any unused provisions in the dash of older T4rs that were made usable in the newer models? For example, my 05 might have a connector with no button assigned to it but finally in 08, they used the connector to make this feature (VSC toggle) work. Are there ever any circumstances that this may be true? I just ordered a factory 08 VSC toggle and noticed an unused connector in my dash that goes to nothing...with my fingers crossed, I'm hoping it was a unused VSC off button that didn't exist quite yet...could it be?