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I drove the 350 several times at the dealer before deciding to buy. Trust me i drove it hard as hell n nasty with big turns and stuff. I never noticed anything weird or less powerful about the drive. WHat is it that trigger VDIM so i know that it is on? On the contrary at Taste of Lexus in miami it was raining so when i drove the 350 there in the rain n did turns it was consistanly on cuz i cudnt gun it and i just knew it was consistantly on cuz i cudnt do nothing with the car basically...so in any case...is it always on or do we as drivers do actions to trigger it?
 

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VDIM is always on, it just engages depending on when it feels wheel slip or excessive body roll.
 

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VDIM is like a caring mother... she's always watching over you... and whenever she thinks you'll get in trouble (even before it happens)... she'll do what she can to keep you on the right path. ;)
 

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Turning trac off will let the wheels spin a little before VDIM kicks in. During test drives we were able to spin the wheels for ~3 or 4 seconds in a corner before VDIM activated. I would guess the reason Lexus put the trac-off button in the car is for people driving on slick ice, where they want the tires to spin while the car is moving slowly so they eventually grip. That's why most RWD cars with traction control have an off button. That usually doesn't take more than a couple seconds, which is probably why VDIM activates if you spin them for longer than ~4 seconds or are above say, 30% slippage.

So turning trac off won't help you circumvent VDIM, but it's useful if you're struggling on ice. :)
 

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Michael said:
Thanks Picus, curious, how long, if at ALL, were you able to spin the rear wheels with trac turned ON? Does the car's VDIM or Trac, give you any wheel spin before cutting power, etc.?
No you can't do that. as soon as wheel spin/slippage is detected, you see the yellow indicator blinking at you. VDIM is a whole system it's not TRAC or VSC. Yes the car's power is retarded with a combination of the ABS being modulated.

For the record. VDIM = IS NOT TRACTION CONTROL. It's a control system that harmonizes all of the features including ABS, TRAC, VSC and etc.
 

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Oh you know, I didn't even bother to check, so that's a good question. If I had to guess I'd say with traction control on it will kick in at a really low slippage percentage, like 15% or something - so you probably wouldn't even notice the tires slipping before it attempted to control them - it probably allows just enough slippage to get a good gripe on say, a wet surface. Just a guess, I could be totally wrong on that one.

Edit - I see flip answered while I was posting, that's pretty much what I figured. I'd leave traction control on all the time unless I needed to turn it off if I was stuck in the snow or on a really icy driveway, or something.
 

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Flipside909 said:
No you can't do that. as soon as wheel spin/slippage is detected, you see the yellow indicator blinking at you. VDIM is a whole system it's not TRAC or VSC. Yes the car's power is retarded with a combination of the ABS being modulated.

For the record. VDIM = IS NOT TRACTION CONTROL. It's a control system that harmonizes all of the features including ABS, TRAC, VSC and etc.

Thanks flipside, so to confirm, by turning Trac off, would you actually be delaying the entire VDIM system for 3 or 4 seconds?
 

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Michael said:
Thanks flipside, so to confirm, by turning Trac off, would you actually be delaying the entire VDIM system for 3 or 4 seconds?
He will be better able to answer but I don't think that's the case. For example, with trac off and the wheels spinning, if VDIM detected some other indicator that the car was out of control it would certainly try to do something about it. I think by turning trac off all you're really doing is letting VDIM allow for a higher slippage percentage under the assumption that you need the tires to spin for a second (to get out of a snow bank or something).
 

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Michael said:
Thanks flipside, so to confirm, by turning Trac off, would you actually be delaying the entire VDIM system for 3 or 4 seconds?
Turning the traction control off does NOT disable VDIM. It just allows the wheels to spin for a moment to get the car out of a slippery situation (like ice). Once the car determines you have regained traction... it switches TRAC back on.
 

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Whats the purpose of building a sports sedan and then taking all the sport out of it? :confused:

There has to be an ECU solution to the problem.
 

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Well apparently you can still throw the car around a bit. And there is a way to turn off VDIM... problem is... nobody outside of Lexus engineering staff knows how to do it.
 

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Crester said:
Well apparently you can still throw the car around a bit. And there is a way to turn off VDIM... problem is... nobody outside of Lexus engineering staff knows how to do it.
As with anything it's just a matter of time till we all know... :cool:
 

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VDIM is always and working. It even will control your steering if you are really out of control. Now it won't turn the wheel, but since the steering is now electric it will adjust the wheels a tiny amount. VDIM was made to where the driver doesn't know it's there.
There are about 3 fuses that say VDIM next to them. I suppose someone could play with those. 1 of them has ABS tied to it. But I know was a standalone fuse.
 

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Impulse said:
Crester said:
Well apparently you can still throw the car around a bit. And there is a way to turn off VDIM... problem is... nobody outside of Lexus engineering staff knows how to do it.
As with anything it's just a matter of time till we all know... :cool:
Anybody who needs motivation to figure out how to turn off VDIM just needs to look at these pics!!!! :jawDrop: :cool:









 

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Crester said:
Anybody who needs motivation to figure out how to turn off VDIM just needs to look at these pics!!!! :jawDrop: :cool:









Whoa...VDIM hard(ly) at work.:jawDrop:
These pics seem to be snapshots of a video though. Now where's that damn video I wanna see it dammit! :loveit::bigSmile:
 

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Thats probably a 250 (which doesn't have VDIM). Read the R&T review of the car and the slalom on it kinda sucked. i'm thinking a supercharged 2.5L would spank the 3.5L.
 
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