aowRS

I found myself in a very slippery muddy situation today, with the truck on a slight slope and wet grass underneath. Had it not been for the REVOs, I would not have been able to get out of the spot I was in. I am well aware of what both TRAC and VSC do - so I am again bringing this subject to the top. The only way I did get going was to have the center diff locked and the pedal mashed to the floor. I did get quite a bit of tirespin, but not without gobs of ABS noise, etc. I have owned the truck since new, and have lived with these issues, but today brought me over the top. If I had been able to defeat both systems, I would have been able to simply floor it and power my way out. Without the center diff locked, the truck just sat there, engine throttled back and the ABS kicking. A few seconds would pass and the computer would allow a bit more spinning before again halting everything. Very, very frustrating!

I know this has come up on many ocassions, so I hope that somebody has made headway with a safe method of temporarilly defeating this crap. Potentially using the factory TRAC OFF switch from the 2WDs.

Let's not have this become another pissing match where everyone attempts to completely define what each system does - it's old news

Andreas

Bluedog

With the center diff locked, one of the two should be off. It snowed tonight and I happend to be in a parking lot and tried it. I think the VSC off light came on.

lee

yea, if you hit that button while in 4wd, itll disengage the vsc.

aowRS

Like I mentioned in my post - I fully understand what the two systems do.

The question remains, how to safely defeat them when basic 4WD is needed? Many people have started this topic in the past, but it has always faded away. The 2WD 4Runners and Tacos have a switch.

Andreas

lee

i dont understand.

if you push the button in 4wd, you have defeated them.

am i just not getting your question?

aowRS

Lee,
Yes - when you lock the center diff, the VSC function is disabled. But the TRAC function remains active and continues to limit wheelspin via the ABS. Even though you can force a certain amount of wheelspin with the center diff locked, the TRAC system will still do its damndest to control spin. There are simply times when powering through something with all four wheels spinning is the best way.

Again, let's not make this into another discussion of what the systems do - its been discussed to death. My post is asking if anyone has figured out the electronics behind the stuff in order to be able to flip a switch and spin the wheels in 4WD - without any electronic involvement.

Andreas

lee

ok, sorry, i must have misread. i too am interested in a solution to this...

2001Millrunner

did anyone try to pull the fuse?

DealMaker

Well, I read somewhere that a magazine test editor determined which relay controls the TRAC and he pulled that relay just to run a few short tests. Problem was, by pulling the relay, he lost the ABS. Perhaps that will give someone with a good electrical background a starting point?

2001Millrunner

If this is true then that'd be perfect, I dont care for ABS too much

Good Times

find out how the trac is being triggered (i.e. wheel spin, abs sensor maybe?) and then make a hardline switch so you can cut the connection when you want.

if the cpu doesn't detect wheelspin then the trac shouldn't engage. ofcourse this ultimately means abs will be disabled. then again how about just removing the abs relay then it won't detect slippage?

just some food for thought

good luck

aowRS

Some good thoughts. Whatever the solution is, it needs to be such that the truck will be back in its normal modes once the switch/fuse/etc is flipped back/replaced/etc. It would be a pain to have to shut the truck off after disabling, in order for TRAC to activate again.

The situations I speak of simply require good old plain Jane 4WD traction and a full throttle. Roostertails. Not for fun, but for getting through crap that would otherwise stop forward movement. ABS, TRAC, VSC, etc are all not necessary at that moment.

I have sung VSC praises before, but for down and dirty full-throttle extraction, I want it all shut down.

Andreas

aowRS

b t t

aowRS

This is the response I received from someone on another forum:

"I unplugged a sensor on the brake master cylinder. This disabled the VSC and traction control but the ABS functions normally. On the Sequoia it was the sensor farthest forward and on the bottom of the master cylinder. If I was to wire in a toggle switch to one of the wires at the sensor I could select off or on."

Does anyone here have thoughts on this? Sounds almost too easy to me.

Andreas

EDGE

drive the subaru next time, problem solved

aowRS

Thanks for the thought. That helped greatly. I'm amazed I did not come to that conclusion on my own.

Dublin

What about wiring in a simple 12v ice cube relay, with the ABS on the normally opened contact and the switch for the VBS wired to the coil of the relay , Then when you turn the VBS off the ABS turns off as well. The ice cube relay would be powering a closed loop when the VBS is on and open loop when off. The relay has 2 sets of open and closed contacts so there are more options. Does this answer the question??

Dr. Zhivago

Have you cracked the hood to actually look at the Master Cylinder to see if there are sensors attached to it that are similar to what the Sequoia owner described? I don't have VSC, otherwise I would be more than happy to help with this directly. But, if it were me, I'd take it upon myself to go look at my Master Cylinder for a start.

If you haven't looked, you're just wasting time.

My .02
G

aowRS

Umm, I intend to. As soon as I have a moment. When I do, I'll post the results. I posted the quote in case anyone had heard of such an apparently easy work-around.

Thanks for your help - the sarcasm helped to get me closer to the actual solution

Andreas

Dr. Zhivago

Well, it seems to me since this topic has had so much press, that SOMEONE would have posted the info already if they had discovered it. AND, since the Sequoia owner is the ONLY person to post such information, I wouldn't, if it were me, waste time posting and waitng for feedback on a public forum on a weekend when people are out doing things... if I was as fed up with VSC as you seem to be.

My slight "jab" at you was to maybe incite you into doing some research on your own with this new-found information. Be a pioneer man!

Sorry if I offended.
G