Vehicle Stability Control

No, and nor would you want to. VSC is a very important safety system. There are only two reasons to ever disable VSC (if you could):

1) Racing.

2) Doing donuts in a snowy parking lot.

Tom

 

VSC is the bomb. It saved me once even though I'm usually a very conservative driver.

My GF's 2001 Avalon has a switch to turn off the VSC, but we have never had a reason to use it.

 

I bet he means traction control... there's no need to even want to dissable vsc unless you're trying to teach your kid how to get out of skids in regular cars...in which case, use a regular car.

If you want to dissable tc, you can (do a seardh on maintenance mode) but you're risking your motor if you do that.

 

Most likely that's it. People get those two mixed up all the time.

Tom

 

Check alignment. It could also be high winds blowing your car around. I think theirs a post around here that recommended getting some of the tires toe in or something to mitigate the your problem.

I've also heard that new tires can also help.

 

+1. Especially check rear alignment. The dealer may not want to deal with the rear alignment because the "official fix" is to replace the axle beam, but I was able to shim mine successfully to fix it.

See here for a thread I hijacked on 2007 Alignment:

http://priuschat.com/forums/gen-ii-...ooting/33373-2007-model-alignment-issues.html

 

I will be very, very surprised if VSC has anything to do with your highway steering issue. When VSC kicks in, it cuts power and applies individual brakes as needed. It doesn't send steering commands to the power steering system.

Is your highway steering issue new or have you had it all along? What type of tires are you running and at what pressure? How many miles on them?

Tom

 

I believe the VSC warning will be ON when VSC detects something.

Ken@Japan

 

Yes, when VSC kicks in there is a warning lamp + audible warning tone.

 

When my rear alignment was messed up, it reminded me of towing our travel trailer. I noticed that different amounts of steering were needed between turning right and left, and I would tend to overcorrect when turning one direction. Shimming the rear to get equal toe in at the rear helped immensely.

 

TC cannot be turned off because it's part of the very essence of the Prius soul! How's that?

The revolutionary THS ( Toyota Hybrid System ) back in the original Gen 1 Prius allowed the electric motor to drive the wheels at times in order to assist the ICE. For example at start up from a stop light.

However what they knew is that electric motors have maximum torque from RPM number 1. Other vehicles have to get rolling and rev the ICE up to 2000 or more likely 4500 RPMs before the max torque kicks in.

The Prius has Max Torque as it's sitting still at a stop light. It's so strong that without a damper on the wheels ( Ta Da ) in the form of Traction Control you or I would hit the GO pedal and our tires would begin to scream and start smoking as the Prius attempted to rip away from the light like a funny car at a drag strip.

To solve this minor issue the engineers built Traction Control into every Prius from the very first one onward. In fact you can't drive efficiently without it. The e-motors are too strong for the vehicle.

 

Yes you need to keep investigating but one your comments leads me to another characteristic of the Prius which is usually unknown before it's been driven quite a few miles.

The Electric Power Steering is uber sensitive. There have been a lot of comments since the first Gen 2s came out that the vehicle drifts and wanders and can't be kept in a straight line. The EPS is very sensitive, there is no play in the wheel at all. Brush the wheel with your coat and it will go left or right.

In fact it is a characteristic of the Prius that needs some adaptation by the driver. It doesn't drive like prior vehicles did. More and more vehicles are going the EPS route because they're simpler, lighter and more accurate ( IMHO ). But they do need constant attention when driving.

I've shifted from having one hand at Noon or 11:30 to a couple of fingers at 6:00. It's more restful and it holds the vehicle straight and on course.

 

This isn't right. At highway speeds, all you need to do is *think* about steering and your Prius should start moving. I drive my 2006 with fingertip pressure. You definitely have a problem. I'd start by looking at the tires.

Tom

 

In this case it's probably your personal vehicle then. As qbee42 noted just above the waves from your eyelash blinking will deflect the steering slightly. Having to fight it to turn would then seems to indicate that there might be something amiss in yours which needs local attention.

 

Yesterday I drove 100+ miles for the first time in my 2006 Prius. I must say that the VSC and ABS etc. did an excellent job of keeping the vehicle going straight down the road. I was driving on the Taconic Parkway down from Albany. For those of you that aren't familiar with the road, it is a 4 lane (2 each way) road built before WWII, that has many curves and steep hills, with narrow lanes. The road was snow covered in the left lane, and just had 2 tire tracks in the right lane. I have the original tires with 45K miles. The car felt solid and maintained good traction the whole trip. I easily past most vehicles I came upon. Definitely one of the best vehicles I have driven in snow.
As far as your specific problems are concerned, I would not go to the dealer, but find a good independent alignment shop in your area. They should adjust both sides so they are symmetrical, not asymmetrical as you indicate, both front and back. It seems like your power assist is not working correctly, maybe you have a blown fuse? It is the 50A fuse #6 in the plastic box on the driver's side under the hood. Are you sure the car was never in an accident?