[flyingwiggler]

I purchased my '09 prius early november and have around 3000 miles on it so far... i've noticed for quite a while that sometimes whenever i brake i'd hear a rattling noise from the front. Does anyone else have this issue or should i have it checked out?

 

[KTPhil]

There is a normal "rattle" noise (some describe it as a "brake fart").

 

[hyperion]

Most noizes emanating from the front of the car complained about by new owners of several months, believe it or not, come from the loose plastic tray insert in the glove compt. It can even make a sound like a loose front bumper bracket.

 

[KTPhil]

Ha! I'd forgotten that tray!

But I bet he's thinking of the brake noise, sort of a farty rattle, , seemingly random, that comes from left left front, and is normal.

 

[texasaltima]

The noise you hear is coming from the brake actuator (the hydraulic power source portion of the brake actuator to be exact)

Consisting of a pump, pump motor, accumulator, relief valve, and accumulator pressure sensor. The hydraulic power source portion generates and stores hdraulic pressure, which the skid contorl ECU uses for controlling braking. The rattling noise you hear is caused by a need for more hydraulic pressure for the accumulator. In stop and go traffic is going to be a lot more noticible, also if you park your car in the garage and wait about three to five minutes you will hear it as well. (you will also hear a vacuum noise coming from the car after a two minutes). Frankly, just be ready to hear a lot of interesting noises from the Prius. Brakes, Coolant Storage Tank, A/C Compressor, EPS, Reverse Gear (BEEP, BEEP, BEEP).

 

[flyingwiggler]

Thanks for the info everyone! Hopefully Toyota can muffle this in the future...

 

[hyperion]

You have to realize that as much as Toyota wants you to believe and operate the Prius as a "normal" car and similar to the other cars in your life, they are not.
Trust that all the strange noises you start to pick up are "normal." Trust the Japanese engineering, and depend on the "idiot" lights on the dash to give you some indication that what you are hearing is "not" normal.
I doubt you will ever see one of those "lights." I know you won't see one when your 12 volt battery is dead!

 

[KTPhil]

I doubt you will ever see one of those "lights." I know you won't see one when your 12 volt battery is dead!

:lol: That's funny!

 

[jfh2005]

There's absolutely NO excuse for that rattle in this day and age.

There's nothing "normal" about the Prius brake actuator noise - it's an infuriating intrusive sound.

Just because Toyota says it's "normal" - it doesn't make it acceptable to me.

They could've easily designed a silent brake actuator part or at least soundproofed it.

Toyota's attitude to these kinds of issues sucks... they don't deserve to have my business at all.

I'm telling people stay to away from buying a Prius.

 

[Phoenix]

If it walks like a duck, and it quacks like a duck...

 

[KTPhil]

There's absolutely NO excuse for that rattle in this day and age.

There's nothing "normal" about the Prius brake actuator noise - it's an infuriating intrusive sound.

Just because Toyota says it's "normal" - it doesn't make it acceptable to me.

They could've easily designed a silent brake actuator part or at least soundproofed it.

Toyota's attitude to these kinds of issues sucks... they don't deserve to have my business at all.

I'm telling people stay to away from buying a Prius.

Good. With your attitude and "I'm the expert on everything including silent brake actuator design" those who know you will consider the source... and figure Toyota must make good cars! :lol:

 

[firepa63]

Don't feed the Troll...

 

[KTPhil]

Yep.

 

[Hep]

Don't feed the Troll...

Yeah, but doesn't that post make any noise your car makes seem less annoying in comparison?

 

[chsim]

Hi, I'm new on this forum & I live in Singapore but I'd like to share some info which might interest you all.
I have a 2nd Gen Prius imported from Japan in May 2008. A few months ago, the chirping sounds started & the mechanics said that the brake actuator is dying. A fortnight ago, the ABS, VSC & brake warning lights came on & the alert sounded. I searched & found that there was a recall for this very problem on Toyota Japan website - toyota.jp/recall/kaisyu/150708.html entitled プリウスなど7車種　ブレーキアクチュエータの修理 which means Prius & 7 other models - Brake Actuator Repair. The phrase "平成15年から平成24年に生産したプリウスなど　7車種の一部車両につきまして、下記内容の修理（無料）を実施させていただくことに致しました。" is saying "Repair (free-of-charge) is in order for Prius & 7 other models manufactured from 2003 to 2012". "ブレーキ頻度の高い厳しい使われ方により、ブレーキアクチュエータのソレノイドバルブシール部が摩耗し、フェールセーフモードに入り、警告灯点灯、警告音吹鳴、ブレーキの効きが低下することがあります。当該現象が発生し修理をご用命の場合、下記の通り無料にて修理対応致します。" means "Due to frequent use of the brakes, the valve seal of the solenoid in the brake actuator gets worn & the system will enter a fail-safe mode with warning lights & sound. Braking performance will be degraded. When such phenomena occur, and repair becomes imperative, you should follow the instructions below to get repairs done free." The part 【 従来の保証期間 】新車を登録した日から5年または10万Km以内 → 【 無料修理対応期間 】平成29年12月末迄：全車無料修理. 平成30年 1月以降：新車を登録した日から9年以内 says that the 5 years or 100,000km warranty is superceded by a free repair period ending Dec 2017 after which this recall applies within 9 years of registration of all new cars. The table of 7 models has Prius at the top of the list. プリウス ZA-NHW20 DAA-NHW20 NHW20-0001002～NHW20-0133242 平成15年 8月～平成16年10月 Aug 2003 to Oct 2004, NHW20-3000002～NHW20-3589297 平成16年 9月～平成23年12月 Sep 2004 to Dec 2011 and NHW20-7000000～NHW20-7894049 平成16年10月～平成21年 3月 Oct 2004 to Mar 2009. My car chassis number is NHW20-3410902 so it is covered under this recall. Yet when I wrote to Toyota Motors for the repair to be done, they claimed that my car (based on VIN) was not part of the recall. I challenged them as I did not reveal my VIN to them. Until now, they are not responding to me. As there are many similar failures, I suspect that Toyota is trying to protect its reputation in its home market but is hoping that nobody else notices that they are treating overseas customers as second class.
Any one has any ideas what we should do to correct the situation?

 

[cathypaladin]

After changing the brakes, the hubs, and anything else we could think of, we finally cured the noise by adding fluid into the transmission. Finally, the noise has went away and haven't heard it again.

 

[Ken Kenney]

This brake noise or as they call it brake fart I have read that it may be a bleed problem on the brakes. The article said to bleed the brakes like Toyota said to do and sometimes the problem goes away. I think that’s why the problem went way when the individual changed all the breaks. Do not believe it had anything to do with transmission. Just a thought Google it and see what you come up with a lot of times they do say it’s the accumulator needs to be changed. That is a big job if you look how it’s done the part alone is about $14-$1500 plus a lot of labor. Just be aware if the light comes on for the ABS it should be changed.