Prius Shuts Down in the Snow, Reader Complains
Toyota Calls Automatic Power Reduction a Safety Feature
January 26, 2007
The Toyota Prius is known to occasionally shut down its hybrid engine system for no apparent reason, wear tires quickly and unevenly, even drain a battery dry when parked for an extended period.
But here's one of the oddest Prius stories on file at ConsumerAffairs.Com:
"When my car is on any kind of slick surface that causes one of the front wheels to slip, ALL power to the drive system is stopped," wrote Christopher of Reston, Virginia.
Christopher said he first experienced the problem with his Prius "on a sloped gravel driveway in July but discounted it as a temporary thing."
Then the snow fell.
"This past weekend I was on a snow-covered road with about an 8- to 10-degree grade. Driving at 20 miles per hour, one tire began to slip on the snow and the car came to a stop. The wheels then refused to engage, because one would slip a little, regardless of throttle position," he wrote.
Christopher tells ConsumerAffairs.Com that he "had cable style tire chains and installed them properly on the front wheels and tried again. Still, a tire would slip on the 4 or 5 inches between the cables and the car would refuse to move."
Ultimately, he said, the only way to get the car up the remainder of the hill was to get out and push while his son put a foot gently on the throttle.
His Toyota service manager told Christopher that he was able to duplicate the symptoms on a level snow covered surface and apparently achieved the same results with two other Prius cars that were in the dealership fleet.
But after reporting the problem to Toyota, the service manager told Christopher that the Prius was operating as designed.
Christopher said that he "will consider this vehicle unsafe for road use under any snow or ice conditions and frankly feel that if all Prius vehicles are designed to do this someone ought to look into the situation to try to force Toyota to modify the design."
Not a Safety Problem
Toyota spokesman Bill Kwon agrees that the traction control systems in the Prius could impact performance in snow conditions but says that is not a safety problem.
"Prius has TRAC (traction control) as standard equipment," he said. "The purpose of traction control is to helps prevent wheel spin and minimize slippage of the drive wheels by applying brakes and/or reducing engine power."
Kwon points out that an 8 to 10 degree grade "is a fairly steep grade and combined with snow would cause a loss of traction which will activate the traction control system and therefore reduce or cut power."
"A vehicle without TRAC in those conditions," Kwon adds. "would probably just start spinning in place and eventually spin out of control. In my opinion, it's better to have the vehicle stop then to have the wheels spinning and out of control."
Report Your Experience
If you've had a bad experience with a consumer product or service, we'd like to hear about it. All complaints are reviewed by class action attorneys and are considered for publication on our site. Knowledge is power! Help spread the word. File your consumer report now.
How is that not a saftey issue.

05 M6 YJ GTO 1 of 447 12.767@109.93
hell my cav moves foward still when the trac kicks in , lol
My traction control on my cav will "give up" after a while.

and just give me how ever much peddle I want.
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
i no thats like a major saftey issue. in my sunfire when the TRAC light would come on the car never shut off. it would try to get traction like it should. it shouldint turn the whole car off lol.
jbody03eco wrote:"A vehicle without TRAC in those conditions," Kwon adds. "would probably just start spinning in place and eventually spin out of control. In my opinion, it's better to have the vehicle stop then to have the wheels spinning and out of control."
Didn't they ever hear of momentum keeping your car going? I used to have to rock my Cavy back and forth all the time to get out of being stuck. Killing power is worthless.
Rob
Sold 2/2/05
I hear it gets excellent gas mileage in that mode though... you know "off" mode.
Its not a bug its a feature!
Tech Tone Blog
Capo di tutti capi wrote:
Its not a bug its a feature!
I am sure that is all they have to say and people will eat it up.

05 M6 YJ GTO 1 of 447 12.767@109.93
Well it is a Toyota, they tend to be like the Macintosh of the Automotive Community.
Tech Tone Blog
Capo di tutti capi wrote:Well it is a Toyota, they tend to be like the Macintosh of the Automotive Community.
Yeah ok...

How many steps to heaven, Doc?
...Ah, metaphysics.
I could of use Linux if that would hurt your feelings less....
Tech Tone Blog
Yeah they do shut right down on ice. Pulling them into my work bay is bit of a hassle when the slope going up to it is all ice. Ive never had it so bad i couldnt get up it though.

"Custom cars, custom problems."-me