On most modern vehicles with anti-lock brakes, slamming on the brakes will cause the brakes to pulse on and off. I had to slam on the brakes the other day on our 2010 Prius, and the brakes didn't pulsate. Is this normal on a Prius, or should the brakes pulsate when applied in an emergency situation?
Try it on some ice, or at least wet conditions. You've really got to lose traction for it to kick in. My recollection, and hopefully I'm not harkening back to a previous car, is a very staccato, machine gun like sound. Geesh that sounds ominous,
The breaks should only pulsate when the tires are about to lose traction. If your car didn't lock into a skid, there was no need for the anti lock breaks to pulsate. If the car did skid, then you need to get your ABS system looked at.
The earliest-generation ABS systems would pulsate pretty noticeably. By the time you get to the system on a Prius, there are several pressure sensors in there and a linear solenoid, and it does its best to just put the right pressure on each brake, rather than banging it on and off. Depending on the exact conditions, you might notice something a bit like pulsing at the very outset, while it's figuring out what the right pressure is. -Chap
When needed, yes they do. You can also feel it in the pedal a little bit (I think so) and should be fairly audible. I have some instances of heavy breaking. When I was test driving my car, before buying it, I got on the brakes pretty good and the panic break assist kicked in and I didn't know about it at the time and I swear the rear kicked out a bit, however there was no pulsing or tire squeal/skid. Not this weekend, but last weekend, "Thumper" ran in front of me, doing at least 40, I slammed the heck out of my brakes (way too late) and the fronts skidded and heard a little bit of pulsing. I didn't slam all the way to a stop though. Another situation I had in the rain, I was coming to a stop sight and no one was behind me and I wanted to test out my brakes in the rain. So I locked them up a bit. Man, the front end of my car was hopping or something. I'm not sure if I've ever locked up the rear wheels. I once too my last car one some country roads to test out the braking ability, it was heavily raining. Would get up to something like 30 mph and try to lock them up, and sometimes try not to lock them up. I still wonder to this day if it's faster to slow down with abs kicking in or not.
