I searched. Couldn't find anything on this. My 2015 Prius with 1,300 miles on it makes a rumble/grumble/moaning/groaning sound after I have come to a complete stop. It can be felt in/on the brake pedal. (Stop light, etc) It lasts for a few seconds then stops.This low rumble has me concerned. It has a slight vibration to it too. (again this is NOT while driving. Only once stopped and foot resting on the brake pedal) I can't confirm it has anything to do with the braking system but seems to come from the general area of the brake pedal and when foot is on the brake. So I assume it's the brake system. I know about the typical brake servo actuator noise (which is completely normal and I am very familiar with) but thats a light unintrusive noise. Distinct from this low grown noise. (I know the difference) I hope I am correct in assuming the computer would detect if there's anything wrong and throw a light... but I'm new to Priuses. Is this a normal sound/vibration? I know these cars do a lot of electric things so if it's normal, I'll try to ignore it.
I'm going to give you the cop out easy advice. Which is since your vehicle is so new, you're still under warranty. Just take it in and have it checked out. Brakes are important enough that I feel it's not worth guessing anyway. If you're at all uncomfortable by anything you perceive, document it, and have the dealership tell you it's OK.
I suppose. I just wanted to know if its a normal thing for the Prius. I really don't like my dealer =(
i don't think it's normal, but maybe i'm just used to it? prius makes some odd sounds, maybe it's the brake accumulator tank. is it at all similar to the buzzing sound when you first open the drivers door?
Yes it's kind of like that now that I think about it. Maybe it sounds different/deeper with the door closed. The brakes themselves feel great. (Well as great as 10" discs can ever feel on 195 series tires) =D
In my case, the noise/rumble happens sort of randomly (a few seconds after I've had the brake pedal depressed) after that servo clickey noise. Maybe it's normal. I'll keep an eye on it or try to record the noise. Maybe I'm just being paranoid.
I'm getting it too. More like a BRRAAAAAP that I can feel through the pedal. It's infrequent, so I can't tell if or when it's going to happen. I doubt Toyota could reproduce the sound on demand. If I had to GUESS, I'd say it's the brake system compensating...perhaps a line is over-pressurized and it let's it equalize the system, but I really don't know.
See if it makes the same noise both with the A/C on and off. For whatever reason (for as long as I've had it) - my A/C compressor sort of "steps up" as I'm coming to a stop, making a grumbling noise, and then a few seconds later (after the stop is complete), it "steps down", back to normal operation. I know, it sounds crazy. I think I saw on here that someone else had a similar problem, some time ago. For whatever reason, I've never had the dealer look at it, and it's continued to be OK. (The car is a 2010, with 120k miles now...) Best luck, Eric
There is a brake fluid pressure pump, electrically driven, in the Prius. When you use the brakes you use up some of that pressure, and when you use up enough the pump runs. It makes the sound you are describing. You may also hear it when you open the drivers door after leaving the car off for some time (typically 10 hours or more). This is the Prius version of "power brakes". The Prius can't use engine vacuum as it can't predict -when- the engine is going to be running, and we wouldn't want to run the engine and use fuel just for power brake pressure!
I've called Toyota's national number. They show no record of this type of issue. So, if I can find a way to get it to happen "on demand," I can run it by the service department and let them look/listen to it.
a great way to test these types of sounds out is drive a new one for comparison. good for peace of mind, or not. i drove my first prius in 2004, and never noticed anything out of the ordinary, or since.
For those who know.... Does frequent engagement of the ABS/TC system lead to any known issues. Mine goes off frequently on my gravel drive (dips in the road surface make a wheel lose good contact), and I wonder if this throws anything off. I don't expect it should. Outside of the driveway, it's really only gone off if I hit a pothole fast enough that the wheel "bounces" over it. I wonder if the "noise" I hear very rarely is just the brake system/ABS "re-calibrating" when the vehicle is stopped and the system sees something out of sorts.
Repeated use of the traction control system will slowly wear the brake pads (it uses individual wheel braking to stabilize the car). As far as I know, that's the only effect.
