2009 noise, noise noise

I believe you're speaking of the brake accumulator pump. If it is, its normal and nothing to worry about. Look up hobbit' prius technical slides on what that's about (I don't think I can sufficiently explain it myself).

 

Yep on both counts.

To the OP: Is the noise the same as when you pump the brakes repeatedly at a stand still? You should be able to trigger it even when the power is off. If so, this is all normal.

 

Brake accumulator pump, as others have stated. The Prius design precludes using vacuum assist for the power brakes, so an electric pump takes over the function.

Your friends 2006 makes the same noise - they all do.

Tom

 

My 2007 FJ Cruiser also makes that noise. Yes, it also has electric assist power brakes

 

Hello Name7:

I'm assuming that you are new to bulletin boards, forums, etc. Next time, please don't use all capitals in your posts, it's the equivalent of "shouting", and will not get your questions anwered any faster, and my irritate other members.

Some Prius' make this sound louder than others. My 2009 didn't make it much at first, but it's gotten a little more noticeable the last thousand mile or so. But I'm used to it; it's actually become a sound that I "expect". Just my little Prius talking to me...

 

Don't they also include a rattlesnake with every car? :madgrin:

 

I like big snakes

 

Sometimes getting the dealer to bleed the brakes on a Prius can reduce the intensity of the noise. There is a TSB out about that. Otherwise, the next step is to replace a few parts. This really isn't a concern for most Prius drivers

 

You're going to have to live with it, its standard noise on all 2004-9 models. I barely notice it much when I drive. Could be because of the radio and/or I'm just used to it.

 

I have to disagree.

We have two 2009s, a base and a touring, and it is only noticable on the touring. It is loud enough that our rear seat passengers are bothered by it and it often interupts our conversation. On the base model, it is so faint you have to listen very closely to hear it. Also, on the base, it doesn't make that sound as often. I'll be taking the touring in for a brake bleed soon to see if that reduces the sound levels.

 

Just make sure a dealership does the brake bleed. It's impossible to properly bleed the accumulator circuit without the Toyota scantool