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VSC Disable

69K views 113 replies 43 participants last post by  01 SolarYellow  
#1 ·
Yes i know I am new. Yes I know how to search.

I just spent about 2 hours looking on how to defeat the VSC. I know you can pull fuse 44.

I want to put a switch in soo that i can deactivate it in the car randomly. Anyone know how this can be accomplished? I see that people have done it but there isn't a how to or anything that i have seen.

Thanks
 
#2 ·
take the fuse out, get some wire and wire up a circuit with the fuse and a switch inline, best place for the switch would be run through the firewall and place it to the left side of the steering column in the switch blanks there. Something like this: male spade terminal in the fuse holder --> fuse --> toggle switch --> another male spade terminal into the other side of the fuse holder. flip the switch to break the circuit and its just like removing the fuse, otherwise, leave it on and all is normal.
 
#3 ·
Ya thats what i was thinking about doing. I read somewhere that someone bypassed a steering input sensor or something. Main concern is I am going to do track days with the car so still kinda want the ABS but no traction control or VSC.

I know a little bit about automotive electronics. Haven't really looked at the IS electrical as I just got the car friday.
 
#6 ·
You know this thread is from 2007 right.......

But hey, you're from a Chicago Suburb so I'll forgive you.
 
#11 ·
ya, i was wondering that too. all i have to do to get sideways is turn off the trac control button.
 
#12 · (Edited)
Hi,

don`t know if you already know this solution to disable the VSC...while keeping full ABS-function...

Get a switch between the ignition supply wire to the steering sensor...

Image


All you need is cut the red/black wire on the Drivers Side J/B, Connector 1A, Pin 4:
Image

and put the switch (nc) in between, like on my drawing.
As a result:
Image

switched off:
Image


CEL was there before, not from this VSC mod!
 
#15 · (Edited)
edit: so, according to the picture, you turn off TCL when VSC is off too?
Yes, both traction and stability control is turned off when you push the 'vsc-off' button.

The ABS, TRC and VSC-functions are all controlled by one abs/trc&vsc-ECU.
If you pull the abs-fuse or relais, the supply to the ecu is cut off and it switches to full failsave-mode. (= all functions off, including ABS).
But if you just switch that ignition supply for the steering sensor off (and you could also eliminate the vsc-buzzer if you wire it like on my plan, because even if you pull a ABS fuse the buzzer still works), there is another failsave-mode with just TRC and VSC off.

To activate the trc/vsc-system again, you must cut of the ignition! (to get out of the failsave mode)
I tested it on snow today and its very funny. No beeping, no warning lights, no "automatic safety reactivating" like when using the stock TRC-off switch, but w/ fully operative braking system.

You have to know that all of our Euro-IS300 models were equipped with VSC, so I`m happy to get rid of that. :cool:
 
#16 ·
Just did this on my Sportcross in prep for a track day. Works perfectly. VSC and TRAC lights come on when the wire is open circuit, and neither VSC or TRAC function. But ABS functions perfectly, and the ECU isn't cutting power or anything strange. This is exactly what I was hoping to find.

Thanks a ton Gery for sharing this with the group!
-Dan
 
#21 ·
did it today...

only shitty part was the switch i had gotten didn't fit between the tabs in the empty spot so i had to cut the upper tab so now the peice is loose, i guess nothing a little bit of tape can't fix
 
#24 ·
Thanks Gery for sharing this!

But...I am a complete noob to this and still a bit confused on the process. lol Can someone explained this in 101 or how to disable VSC but with abs active for dummies point of view? lol
 
#26 ·
Does this still leave ABS activated?

I just noticed the CEL....Is this what happens with this VSC disable or was that cel from something else?
 
#27 ·
It doesn't cause a CEL, he must have had that from something else.

I did it today, no CEL, ABS works great, no buzzer, Traction control and VSC no longer work. I didn't put a switch in yet, instead I just clipped the wire and installed a male and female crimp connector.

I ordered a VSC off switch from a 4runner today, I'm going to make sure it fits tomorrow and then I'm going to wire that up to turn it on and off. I will either need to modify the switch internally or buy a module from Token to change it into a toggle switch however, as the button itself is a momentary switch like our TRAC off button.

I figure it will probably fit nicely over in the left side of the steering wheel and give a nice oem touch.
 
#28 ·
It doesn't cause a CEL, he must have had that from something else.
Right, the CEL on my pics was because of my auto to manual conversion, the VSC-off mod will not cause a CEL.

I ordered a VSC off switch from a 4runner today, I'm going to make sure it fits tomorrow and then I'm going to wire that up to turn it on and off. I will either need to modify the switch internally or buy a module from Token to change it into a toggle switch however, as the button itself is a momentary switch like our TRAC off button.
Nice idea, post some pics when finished. You don't need to modify the momentary switch since the VSC system is disabled as soon as the B-R wire is disconnected, right?
If you want to reactivate the VSC by pushing the button again it would get a bit more complicated as you have to reset the VSC ECU first (ignition off and on).
 
#30 ·
Talked to Shaun at Token - very helpful guy as always (I just got airbag sims from him and between that and my O2 delete from him...my car is still running without error for years now).

Anyhow, he said the trac module he has won't work (or wouldn't be best). I'm going to scheme with him after I get a little more info on the OEM VSC off switch tomorrow or the next day - whenever I get the switch in my hand.

Has anyone tried this with the car running, that is, breaking the circuit? I'm wondering if I couldn't just wire it up so that the momentary switch BREAKS the circuit rather than connects it so you'd just have to hit it to disable VSC with the car running.

Getting it to re-enable while the car is running could probably be done, though I have no idea how. The best I could figure though is you would just need to reconnect the circuit, and then power cycle the VSC/ABS/TRAC computer only. In other words, make that unit think the car was turned off and then back on. I have no idea if this would safe to do though, especially while in motion (not sure what the unit does when it self checks, etc).

Nathan
 
#31 ·
Good description, Nathan. That's exactly what I'm thinking of.
Maybe you are able to get a normaly closed momentary push button or you just use a relay/electronic device to invert the signal.

As for "power cycling" the VSC ECU, I don't expect safety issues, the only thing that would't work is the ABS system while you reset the ECU, but that is just for a split of a second. It's the same as a for example a blown ABS fuse, the ECU always reacts "failsafe".
 
#35 ·
Gery,

where'd you get that diagram from? I am wondering if you can help me figure out what the best place to place a momentary switch would be to power cycle that ECU.
Unfortunately the link to download the diagrams is down...
Reset the ignition supply from the VSC computer, see 'reset sw' below

Image


If you use 2 switches it won't be a problem, else you will need a little blackbox...
You could use the VSC warning light output (GND when VSC off) from the VSC ECU for a blackbox circuit to only power cycle when the VSC is off, it is the output B/14.