Toyota is in hot water over a safety system that isn't performing as advertised.

Last month, the Insurance Institute for Highway Safety (IIHS) released its ratings of frontal-crash prevention systems. Some cars excelled in the new tests, others didn't.

One car that didn't do so well was the Toyota Prius V hybrid wagon.

Toyota offers its Pre-Collision System (PCS) as on option on the Prius V; it's supposed to be able to brake the car at certain speeds if it detects something in the vehicle's path, to lessen or potentially avert frontal collisions.

"The Toyota Prius V wagon, which claims to have autobrake, had minimal braking in IIHS tests and currently fails to meet NHTSA criteria for forward collision warning," the Institute said.

"It doesn't qualify for an IIHS front crash prevention rating."

2012 Toyota Prius v

2012 Toyota Prius v

To make matters worse, the system is a pricey item. PCS is part of the $5,650 Advanced Technology Package, which is only available on the top Prius V Five model.

Naturally, after seeing the IIHS test results, some Prius V owners feel they aren't getting what they paid for.

And so they're suing Toyota.

In a press release, the plaintiffs claims $1,000 of the $5,650 Advanced Technology Package is attributable to PCS. They want Toyota to reimburse them for that $1,000, and change its advertising to reflect the IIHS findings more accurately.

The plaintiffs have asked that their case be granted class-action status.

Interestingly, the plaintiffs are represented by the McCuneWright law firm in California.

That's the same firm that recently settled a $1.6 billion class-action case against Toyota for unintended acceleration, and also filed class-action suits against Ford, Hyundai, and Kia for exaggerated fuel economy claims.


Follow GreenCarReports on Facebook, Twitter, and Google+.