Toyota Motor Corporation Complaint - Prius 2004-2008; Major Safety Problems
I have a 2005 Prius and generally love the car. But it has two major safety flaws. Toyota has known about these flaws for several years, but has not fixed them. They relate to traction control and seat height.
The Prius has a traction control system that brings the drive wheels to a full stop when it senses slippage. This puts the car in dangerous, sometimes life threatening situations when trying to drive up slippery hills. The first rule of making it up a slippery (ie: snowy) hill is, don't stop. If you lose momentum, you probably won't regain it. Instead you'll have to back down and try again.
When going up a snowy hill in the Prius, if the wheels slip, the tires come to a full stop, which often brings the car to a full stop. Sometimes the car starts to slide backwards and the driver has no control. Good drivers know how to maintain just enough wheel spin to keep the car moving. The Prius takes this option away from the driver.
Apparently the system was designed to protect the hybrid system. But it's more important to protect the driver and passengers. The traction control should be converted to limited slip, like the FJ Cruiser.
Due to the traction control system that brings the wheels to a full stop, the Prius may be the worst car in the world at making it up snow covered, gravel or other slippery hills.
The second problem is that the US Prius does not have driver's seat height adjustment. Prius's in Japan, Europe and Australia have it. Less expensive US Toyota cars (Yaris, Corolla, Camry) have height adjustment. But every model Prius, even the most expensive, does not have it.
Aside from being uncomfortable, it creates a hazard for tall and short drivers. The Prius roof slopes down in the front and back. Because tall drivers cannot lower the seat, they sit too high in the car. This restricts their vision out of the front and rear windshields. Because short drivers cannot raise the seat, their vision is restricted as well.
At least two thirds of Prius drivers would use the height adjustment feature if it was available. It's hard to imagine a feature that provides greater driver comfort for less cost. It's also hard to imagine why driver's seat height adjustment was not put on the $30,000 high end Prius, when it was put on the $13,000 base model Yaris sedan.