Note to toyota corp: Wifey is complaining about VSC

<div class='quotetop'>QUOTE(syncmaster @ Jan 16 2007, 11:57 AM) [snapback]376285[/snapback]</div>

I'm guessing this has less to do with the rain and more to do with loose, uneven surface. I'm not sure how she drives but slowing down or accelerating a little softer would probably help.

I said the same thing but ultimately just couldn't justify waiting to make the change just because there was tread left on the (no-) Intergrities. I only had 14k on mine and I'm sure they probably would have lasted another 20k but the TTs come with an 80k warranty and peace of mind.

 

I've never had that problem on wet roads. I suspect that she simply accelerated too hard. I can get the wheels to almost spin on dry roads when accelerating from a stop into a turn. On a wet road, it's almost a sure thing. If the road has gravel or a very uneven surface, it's easier to spin the wheels.

I believe it was the traction control that kicked in to avoid wheel spin. It doesn't know why the wheels are spinning, just that they are.

Just have her lighten up. Best thing? Have her demo it to you. I expect you'll find she's accelerating too hard for that turn.

 

now and again, when the coast is clear, I'll take a corner, or accelerate to where the traction control kicks in just so I get more used to how it feels when it does.

Either she's going at it with some ghusto, or there is something different between your car and mine.

If she wasn't expecting it, I'd guess it didn't feel good to her and thus the complaint.

When I do kick in the traction control, I feel it in the steering, but no... absolutely not as far as the car going to take me into the ditch or have to fight the thing to keep control.... just feedback into the wheel.

I'm sure there is room for Toyota to take what they have, improve the software and make it better or smoother, but in the end, there is nothing wrong with what they deployed in the prius we all have right now.

 

<div class='quotetop'>QUOTE(syncmaster @ Jan 16 2007, 11:57 AM) [snapback]376285[/snapback]</div>

This strikes me as unusual. Traction control works by limiting power to the wheels, and VSC works by applying individual brakes to drag the car back in line during a skid. Neither of those features has any direct impact on the steering wheel.

If she didn't hear the VSC beeping and see the icon flashing then it probably wasn't that. (What would cause VSC to engage from a stop unless she was REALLY giving it power, anyway?) And traction control feels more like an engine stall...the pedal goes down but the car doesn't do much about it.

If she truly had to wrestle with the steering wheel then I would be hard-pressed to write it off without further investigation. The other possibility is that her isn't entirely accurate, which is not unusual the first time something strange happens.

 

I ahve read that VSC, in addition to applying individual wheel brakes, can also modify the power steering effect to make it harder to turn in the "wrong" direction to avoid a skid.

 

I've had wheel slip problems on wet pavement when starting up- the foot was a bit too heavy on the gas and the pavement uneven...... :blink: The motors are very powerful and it's easy to spin the wheels on wet pavement.

 

<div class='quotetop'>QUOTE(syncmaster @ Jan 16 2007, 11:57 AM) [snapback]376285[/snapback]</div>

i hate to point this out and all... but if you're accelerating from a stop and the car doesn't go where you want it to go it's rather simple to take one's foot off the accelerator. or put it on the brake. or both. i think she was just a bit upset about the unexpected experience and the whole "struggling for her life" comment was a reaction to such.

vsc has no control over steering in your prius. so if the wheel didn't want to turn, that's something else. have you driven it since? anything feel different?

<div class='quotetop'>QUOTE(KTPhil @ Jan 16 2007, 01:37 PM) [snapback]376356[/snapback]</div>

not in the current toyotas. this is true for the new generation of lexus vehicles.

 

i saw a video today of a 4 wheel drive SUV sliding down a street in Portland, OR. it hit about 7 cars...actually hit 4 cars but pushed one car into 3 other cars.

 

<div class='quotetop'>QUOTE(DaveinOlyWA @ Jan 16 2007, 07:36 PM) [snapback]376618[/snapback]</div>

Was that because of VSC? Traction control? Or just someone sliding on ice? Does it apply here at all?

 

<div class='quotetop'>QUOTE(Rick Auricchio @ Jan 16 2007, 10:24 PM) [snapback]376669[/snapback]</div>

I believe the video is the one seen at http://priuschat.com/index.php?showtopic=28509&hl.

 

I'm not a fan of VSC myself. If the car is going to have it, at least have the ability to turn it off like in most other cars.

 

<div class='quotetop'>QUOTE(syncmaster @ Jan 16 2007, 11:57 AM) [snapback]376285[/snapback]</div>

A relevant VSC experience was posted here some months back:

http://priuschat.com/index.php?showtopic=1...mp;#entry203613


In that thread, the same comments came up, notably that VSC and traction control deal with the brakes, and don't take over the steering.

My two cents is that, at one point, for a job, I ended up driving a total unsafe clunker with bad brakes. And I can say from scary personal experience that if the brakes fail on one wheel only, that can jerk the wheel right out of your hand, even at low speed. I believe that's why cars were (maybe still are) designed with "dual diagnonal" brake, so that if one braking circuit fails, you lose braking on one wheel on the front and one wheel on the back.

I vaguely recall reports of other similar experiences here, but this is the one that stuck in my mind. It was not the Prius, but the report of a VSC problem in a 4runner that actually described the faulty part.

VSC is designed to take over control of the car. It seems plausible that a VSC malfunction would -- take over control of the car. The thread mentioned a defective yaw sensor for the 4runner. Absent better info that's what I'd look for first.

 

For those who think the VSC doesn't include a steering component, it most certainly does.

It's been noted since the very beginning.

Toyota Launches All-new Prius

The new Prius achieves outstanding maneuverability and cruising stability by adopting the world's first* Steering-assisted Vehicle Stability Control system (S-VSC), based on Toyota's cutting-edge hybrid control technology.

It won't 'steer' the car but it does increase the resistance to steering in directions that would induce or exacerbate a skid.

Another Link

Toyota Prius Crash Test

Class leading active safety

Besides being a D-segment top peformer in passive safety, Toyota Prius also intends to set an example in the area of active safety. For this reason, it is fitted as standard with features that are unique in the class: ’by-wire’ Electronically Controlled Braking (ECB2), Electric Traction Control (E-TRC) and the advanced Vehicle Stability Control Plus (VSC+).

The innovative ’by-wire’ ECB2 braking system uses brake pedal-activated electronic sensors to create braking feel and control the braking hydraulics. It not only generates higher hydraulic pressures than conventional systems, but it is also 17% lighter.

The Prius is the world’s first car to be fitted with Electric Traction Control (E-TRC). The system controls wheel slippage via ECB2 and the high-torque electric motor element of the Hybrid Synergy Drive. E-TRC is so quick in counteracting the incipient skid that the driver often won’t even be aware of an intervention, nor will he or she hear the tyre squealing that is often associated with wheel spin.

Interconnected with ECB2 and E-TRC is Vehicle Stability Control Plus (VSC+) which is the world’s most innovative stability control system. It works with the electric power steering system (EPS) to add steering torque assistance to the conventional stability control system, helping the driver get the most out of the car’s performance potential by avoiding stability-threatening situations.

Yes, it is on Lexuses, but it was on the Prius First

 

<div class='quotetop'>QUOTE(Tempus @ Jan 17 2007, 11:00 AM) [snapback]376767[/snapback]</div>

Thank you, that was a good clarification. All the more then, these occasional posts of episodes like this could plausibly be due to occational malfunctions of the VSC and related systems. The thread I cited above mentioned over-sensitivity of the VSC as a generic Toyota problem.

My only other comment is that presence of ABS/VSC/traction control on this car has made me drive more cautiously, not less. It's skittish, and it never fails to scare or annoy me when I lose the brakes or gas for that split-second while the car does whatever it does. Ever time I trigger it, I try to remember never to do that again without getting ready for a possible VSC/ABS/traction reaction. So far my list consists of:
a) brake while going downhill over a pothole
b) brake while driving from pavement to gravel shoulder
c) accelerate while moving from gravel drive to pavement

I think this is the second post I've seen with:
d) accelerate while turning (uphill?) from a dead stop on (possible less-than-optimal) pavement.

And the thread I referenced mentioned for a 4runner:
e) sharp turn on bumpy pavement.

Several people have posted a) and c). Maybe we ought to keep a list, we could just reference it the next time one of these gets posted.

 

unfortunately many people do not grasp the concept of variable acceleration techniques and give the same amount of gas for every situation, including in different weather.

 

Google "Toyota vsc problem" and read some of the posts. My take on it is that VSC can be a real hazard if it malfunctions, and as with all machines, its more likely to malfunction as the vehicle ages.

But what I'm trying to get at is that a malfunction here is quite different from your normal failure of a part on a car. It fails without warning and puts you in jeopardy, and it's seldom going to be clear that it is a malfunction.

The only thing I could liken it to would be having a tie rod end break on the front end. No warning followed by loss of control. All you can do is hope you're going slowly at the time. But even then, you can see the broken part. You can inspect ahead of time, you can expect to wear, and the fix is unambiguous.

Instead, this is like having a possible intermittent short in your electrical system, except you're not quite sure whether you have a problem or not, and it might kill you.

So have a little sympathy for the poster. This didn't sound like driver error to me. So, here he sits with a $20,000 vehicle, wondering a) whether the VSC is or is not screwed up, but most importantly b) if it is screwed up, whether somebody's going to get hurt the next time it misfires. Sell it or not? Wait for another misfire? Definitely have the dealer check it out.

I've driven so many clunkers that I thought I'd hit about every type of car probem you could get, but I now realize they are inventing new ones.

 

All good things must come to an end. My TripleTreds have started to slip under various conditions, like at wet intersections where lots of cars have left rubber behind, and the occasional standing-start-turn at a stop sign. Dry roads with no loose gravel are still handled well.

At maybe 32,000 miles of use I still expected the wet handling to overcome this stuff. Next time I'll have to try the Michelins...

 

<div class='quotetop'>QUOTE(galaxee @ Jan 16 2007, 10:13 PM) [snapback]376608[/snapback]</div>

ok, misunderstanding. the prius and other toyotas can not actually steer the car *for* you. that's what he thought was being discussed. (this is apparently available in new lexus models and is a hot topic, hence his immediate thought of that.) my fault, sorry bout that.

yes, the vsc can *influence* the eps motor.

at any rate, all these comments about vsc kinda make me glad we don't have it