LeeD

Just found this over the weekend in the technical manual,

FYI, I will not be held responsible if you destroy your ECU or any other components in your car. Do this at your own risk. I've done with good results on my 2005 xA RS 1.0, and ONLY have verified it on that car.

To disable VSC.
1. Turn off the car.
2. Find the service jack. It's located under the fuse box to the bottom left of the steering wheel.
3. Take a wire and jumper pins 4 and 12. These are located around the middle of the connector. Count around 4 pins from the left on the top row and the bottom row. These should be the first ports that have electrical jacks in them. You jumper the top to bottom.

4. Turn the car on and you should see VSC and ABS blinking.

It is now disabled. Pulling the jumper out keeps it disabled. The next time you shut off the car and turn it back on, it will reset and be enabled again.

Cheers,

striker79

what are pins 4 and 12 responsible for exactly? could you get a picture of this diagram in the manual.

hotbox05

yes , please snap a pic.

LeeD

The service manual just mentions pin 4 is CG (Common Ground), but I couldn't find anything on what pin 12 was. I looked through the entire document for a full electrical schematic similar to what I've seen in the service manual for my Z, but nothing in this one for the xA.

The service manual explicately mentions to install SST #####-#### to DLC3 (service port) and that this specific SST would connect to these two pins. After installing SST and turning on the car, it will disable VSC and you should see it blinking to indicate it's disabled.

For me, ABS was also blinking, but it didn't say anything about about. I'm just assuming it's disabled even though somewhere else in the manual it says when it's always on, then it's no working and off. Not that when it's blinking it's disabled.

I was very nervous at first about just jumpering the 2 pins together, not knowing what pin 12 was. Knowing this was a service access port to see everything on how the engine was running, and should be fairly standard, I tried to find the pin out of it over the internet. What I found was that the pin-out for the port is standard (to a degree), and actually not all the pins are used for Engine/car diagnostics. Since communication is serial, there's just a Com-in, Com-out, power, ground, and maybe one more pin used. Pin 12 was used for any of that, so I assumed it was something special that Toyota wired. Using my Electrical Engineering background and my own work background, I figured they'd either install a resistor to induce a voltage, or a jumper. I think the odds are pretty low that they would make it so difficult for technicians by making it a resistor, as it's required to install this SST if you put it on some hub measureing equipment. Making it a jumper releaves the techs from purchasing multipes of these SSTs for a shop. The SST only prevents you from installing the jumper in the wrong position.

With that, I took the leap of faith and just assumed SST was just a simple wire jumper inside (as I've seen done on numerous other similar devices). Installed the jumper wire and bingo, it worked.

I saved the page as a bmp on my home computer so I can reference in the future, but right now I'm at work. I tried looking through the service manual again to give the page number to you guys, but I can't seem to find it now. Naviation online isn't all that fast either...

Folks, I totally understand if your sceptical. I would be too. But if you don't want to do it on my word, then that's fine. I'll be testing this out personaly in about 2 weeks.

Not to be rude, but people, don't expect me to know if this will work for a xA manual, xB auto/manual, tC auto/manual, etc.... I can only say this works for an xA RS 1.0 auto. If you want to know how it's done on your car, go put some money down like I did, get a manual, like I did, and do your own leg work, like I did. :D It took me a few hours of flipping through pages on-line to find and get enough confidence to do this.

LeeD

Not sure if it's OK or not with the mods as it's a paid ScionLife service to get access to this, but, here it is,

It's on page, 1-17 of the service manual.

hotbox05

maybe it's ok maybe it's not but yer pic isnt workin lol.

ProtoCulture

Can't have VSC turned off without also turning off the anti-lock system. The two systems are interlocked and integrated. The way the VSC works is when wheel slip is detected and it applies the brakes is a specific manner to regain control of the vehicle. That is why the ABS is also blinking when you do this mod. You can't have one without the other. More likely what happened is that the mod as described probably took the ABS off, which in turn disables the VSC, rather than the other way around.

A broader question is why would you want to disable either system? These cars do not have enough power to require use of the VSC in a high grip (read clean dry road) to gain any use from the wheel slip advantage in say, an auto-x. The only time the VSC may even turn on at all might be a low grip (read wet/icy). Great discovery, but I can't think of a practical reason to turn it off.

Thanks!

hotbox05

no the vsc beeps all the time if u drive it hard enough lol. and abs isnt good fro racing , why u think the pro's don't use it?

ProtoCulture

In fact there are some racing cars that do use ABS. There are also some racing sactioning bodies that do not allow ABS. Most racing does not allow VSC or other forms of electronic control that might give drivers an unfair advantgage (launch control, which is a form of VSC, is banned from most professional drag racing).

While I agree that in most motorsports, enabled ABS is not the fastest way around a course, I stick by my assertion that our cars are not really powerful enough to take advantage of such. Sure that VSC may be blinking, but I would submit that low powered vehicles such as ours will not see a significant difference with it on or not. We simply do not have the power to really roast our tires around a corner

hotbox05

it's all about the power you bring to the plate. by the time i get to an autox course i will have too much power to keep the ____ty vsc on. thats just me tho , it'll be good to see leed's results having auto-x'd before and after. we can see how his results are.

LeeD

Reference the title to the thread, "How to disable VSC for proper drifting. " :D

Yes, I totally understand how the VSC works and what it does. I've felt it working over time numerous times the last time I was at the track. https://www.scionlife.com/forums/vie...44fbbd1c5e8d2d Something else that it does, that you didn't mention is that it also cuts the engine hp. Nothing abrupt, and it doesn't seem to do it until after it applies the brakes on the corners to bring the car straight. I was finding that it was cutting the hp and applying brakes so much that I would loose momentum when I was drifting and eventually would just straighten out and drive out of the turn because I was going so slow.

January 29th, 30th, I'm organizing a 2 day track driving school/event and that's where I plan on testing it out.

By the way, I think I could do it in the dry as I've trailbraked drifted in the dry on Zs, but it's more fun and less tire wear in the wet. I hope it rains the WHOLE WEEKEND!

btw, although it seems to disable the ABS with the VSC, I'm not giving up in trying to figure out how to keep the ABS. In the rain, I'd like to keep the ABS. Especially so since the brakes aren't very linear (more like logrithmic!) and may be difficult to modulate. I'm definately going to try it though and just feel things out and have fun.

fyi, the whole drifting ain't fast, yes it is, it's in racing, no it's not, blah blah has been beaten to death already in the Autosports & Technique forum... I have no intention of disabling it during an autox, if/when I do take it to the autox.

squirrel

Nice find Lee!

LeeD

Hp only gets you to the turn. How to use the brakes and steering will define if you induce VSC. Of course higher hp will help to induce it more, but a stock car should still be able to induce VSC at autoxs.

I think the VSC is actually pretty good and not too intrusive or abrupt in what it does. I'm only complaining about it because I'm TRYING to slid the car and am holding fairly healthly slip angles for long periods of time. I find that while "driving" the drift at turn in, apex, and exit, it's very difficult to "drive" it at the same time as I'm fighting it to hold the drift. My driving line gets all screwed up and changes continually while ON the line because I'm fighting with the VSC.

hotbox05

just a question leed , arent u on auto tranny? why auto x with auto?

DarkBoxJr

Lots of people AutoX with autos. Just keep it in 2nd.

its_ikon

hmmm, drifting in a fwd?

LeeD

(just trying these new emoticons )
Yep, some just keep it in 2nd, or even 1st and then let the tranny shift to 2nd by itself.

No, auto trannys are not the ideal, but they still work ok for autoxing and for the track...

I have yet to autox my xA yet. All my past autoxing has been in the Z.

pkoule

Great post, Lee! Super information!! Good find..

I can't help but think that Toyota put in the VSC to keep us from getting all sideways in our tall, narrow xBs and barrel-rolling them down the street.

(mercedes implemented a similar safety in one of their SUV/Soccer vans a few years ago, remember?)

That added feature cost Toyota little to put in, and no doubt saves them plenty in liability coverage!

Not that the xB isn't a blast to drive, but it's never going to be a skidpad champion.

ProtoCulture

Great discussion here and a great find LeeD. I look forward to your findings on the track. Also, good luck with finding a way to keep only the ABS. That would be fantastic.

striker79

yeah lee i belived you and all as i come from a automotive back ground i just wanted to know what the pins controlled and if 12 is ground thats great to know so thanks because no it opens up more possibiltys for certain things.what i don't know yet but who cares if i run into something i'll now know a little more than i did before and there's nothing wrong with that as far as i can tell.so cool find thanks