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This has happened several times (and it's very scary!)

The car hits a pothole or bump and the anti-skid warning comes on for a second or too. I'm not even sure if my foot was on the brake.
However, the Prius seems to lurch ahead, as if it's moving from under me. Had there been a car in front of me, we would have had an accident. Both times, I was going slowly (20 mph ish).

Has this happened to anyone?

Thanks in advance.

David
 

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No, it hasn't happened to me with my 2005, and I'm glad. That would scare me to death.
 

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It's not the Vehicle Stability Control (that one comes with a beep). A "skid" icon without a beep is the traction control. Yes, it does that sometimes especially when it's wet. It seems like it lurches forward cause the brakes come on, then go off.
 

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If you foot was not on the brake, I would take it to a dealer to have it checked out. Even if your foot was on the brake, it still sounds like something is wrong. I have never experienced anything like that with my 04.
 

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drtravel47 said:
This has happened several times (and it's very scary!)

The car hits a pothole or bump and the anti-skid warning comes on for a second or too. I'm not even sure if my foot was on the brake.
However, the Prius seems to lurch ahead, as if it's moving from under me. Had there been a car in front of me, we would have had an accident. Both times, I was going slowly (20 mph ish).
I am starting to read posts like this in the prius forums. I also drive a ford e350 van and have the same problem with it when approuching a red light and apply the brakes and run over bumps and/or gravel the ABS cuts in and suddenly the van is not stopping fast enough, at that point I have to apply alot more pressure on the brake and that overrides the ABS and stops the van.
It is understandable what is happening the wheel is bounced into the air from a bump and the wheel locks for a half a second , the ABS computer will sense the wheel locking and activate the ABS. I do think it happens very rarely and usually when I was going to fast and having to brake hard to make the stop.
This is the price we pay for having the ABS braking system... no system is perfect !
 

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ABS Problems Contribute to Low Speed Crashes

I don't know if this is an actual problem, or whether it may be caused by the ABS system; but apparently other auto manufacturers are having similar experiences. See article on GM, below:

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GM Recalls Trucks & SUVs for ABS Problem
August 30, 2005

General Motors Corp. is recalling 804,000 full-size pickup trucks and sport utility vehicles because of potential problems with the anti-lock braking system.

Problems with the antilock brake system are behind the GM decision to recall vehicles in 14 northern states. Corrosion in the braking system is blamed for more than 200 low-speed crashes.

A GM spokesman says the problem occurs when salt and other road grime gets into the area covering the antilock braking system sensor near the wheel hub. The problem activates the ABS at speeds much lower than normal, requiring a longer stopping distance.

The National Highway Traffic Safety Administration (NHTSA) describers the problem as an unwanted application of the antilock brake system. NHTSA opened an investigation in late April of more than 1.2 million GM pickups and SUVs in 20 states because of questions about the antilock brakes. The investigation is still underway.

Vehicles involved in the recall include the Chevrolet Avalanche and Silverado pickups and the Chevrolet Suburban and Tahoe SUVs. The GMC Sierra pickup and Yukon and Yukon XL SUVs are also affected. All 804,000 vehicles trucks are from the 1999-2002 model years, NHTSA said.

GM says there have been 228 crashes reported through the end of May, including 10 minor injuries.
 

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Not the VSC, but the traction control. Happens on all Prius when braking, and you hit a disturbance in the road (like a pothole or maintenance cover). The wheel that hits the disturbance temporarily becomes airborne, spinning faster than the other wheels (like if you hit a patch of ice). The traction control for safety reasons shuts off the regenerative braking, switching over to entirely conventional hydrolic braking. Unfortunately, this switchover isn't completely seamless, so for a split second it may feel like your car lurches forward as you have a moment of less braking force than you were expecting. After a while of ownership, you'll anticipate this happening and instinctively apply the brakes a little more when going over a pothole and you won't notice the "lurch."
 

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yeah what the guy upstairs said. but i always thought vehicle skid control was the same as traction control. you learn something new everyday :D
 

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ABS=Brakes. Prevents wheel lockup when applying brakes. In other words, keep all wheels spinning evenly when they stop. You get the skid lamp without sound when this happens.

Trac=Acceleration or cruising. Prevents wheels from overspinning when traction is lost. In other words, slow or stop wheels when they spin out of control relative to the other wheels. Since this is a front wheel drive car, this can only happen with front wheels. You get the skid lamp without sound when this happens.

VSC=Turns. A combination of Trac oand ABS, but uses yaw sensors and steering angle sensors to prevent the car from fishtailing. If the car senses the car is turning more than you told it to, it will take corrective action. The skid lamp will light with a buzzer when this happens.
 

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Unless I have a bad experience, I usually ride over railroad tracks at the posted speed. One set of tracks is up a hill, and as I cross them at 45MPH sometiimes the VSC light comes on. (It's not often traffic is flowing freely enough to let me go the posted limit.) I guess it doesn't like the tires spinning in mid-air. I notice no lurch, but maybe I would if all of the tires were on the ground.

Other than that, I've seen the VSC light come on once on a wet, curvy road where it deserved to come on because I hadn't compensated for the curve or the wetness...
 

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Hmmm...that happened to me just a couple of days ago and I thought I had imagined things. I'll wait to see if it happens again before I do anything about it, though.
 
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