Braking switch over potholes issue/non-issue update

The "feeling" of momentary loss or switch over does exist. It's a Prius thing...you get used to it or get rid of it.

 

I too have experience this, I learned the best way to brake is to start braking earlier than a normal car. One time I braked over a pothole and my car felt like it skid about 2-3 seconds.

 

The ABS module cutting in is the cause of this feel issue.

Simple explanation: When you hit a bump - hybrid regen braking is cancelled, and the ABS uses hydraulic-only braking.

The top part of the travel of the brake pedal is what signals to the hybrid module to regen brake to collect power to charge your hybrid battery. This can take up to 100 amps into the battery according to the scangauge in my Prius C.

If you hit a pothole, it can trigger the car's ABS system. It's especially sensitive to this if you have your tire pressure set higher than the factory spec.

When the ABS system is active, regen braking is totally disabled. If you were already braking when you hit the pothole, you'll feel the pedal resistance disappear, and it will travel down to the hydraulic braking zone of the pedal travel. Then the ABS will help you stop the car.

Regen braking will not work again until your car comes to a complete stop - so often if you hit a pothole while braking, the brakes will feel different for a while until you stop.

The recall in 2010 addressed this by reducing the sensitivity of the ABS engagement at low speeds.