Horn problem

no, it's normal. Someone else with proper terms will explain this to you.

 

are you SURE it's the horn? the interior will beep at you if you aren't buckled up when you start the car...

 

Wow! This has been happening to me, but I wasn't sure what the problem was.

Sort of like the voices that speak to me in my head...

 

are you sure it's from the horn?

 

The "chirping" also occurs on my 2004 when stepping on the brakes at a light (occassional, short - almost aborted - honks); it is quite intermittent. While it sounds like the horn is the cause I don't know if it is really the culprit. I have wondered whether it might be more directly related to the brakes.

 

Stop it, cousin Tony, you're hurting the car!

I have never heard of phantom beeps in the 2001-2003 Prius. That new model is really...different.

 

I think what your hearing is the brake accumulator pump. Have someone get in the car and with the hood open have them press on the brake pedal firmly you'll probably hear a sort of pulsing sound coming from the right hand side of the engine compartment. Running or stopped it'll do it.

 

Wow, this is interesting---just when you think you've heard it all about Priuses, now three owners jump up and reveal yet another mystery.

The fact that two others confirmed the original poster so quickly ordinarily would tell us that it's a widespread "phenomenon" (if not problem), and that there should be a simple explanation (and even fix, if necessary). Hmmm. I have an '04 and have never heard it, but I have a 40% hearing loss. The only unusual noise I remember hearing about from that area of the car is a "thermos bottle" noise, and I think that's only, or primarily, when shutting the car down.

Guess I'll go stand on my brakes tomorrow and turn my hearing aid up.

 

When the car has just been shut off, about 5 minutes later you may hear a hissing sound, followed by a compressor type of noise, which is probably the 'horn' noise you are describing. The hissing would be the valves releasing brake pressure, followed by the accumulator pump replacing the pressure. This helps prevent air in the lines.

Now if you hear the pump run too often, you may have a slow internal leak in the accumulator. The pump should not run more than once if you haven't operated the brake. If you do operate the brake, you are using up reserve brake fluid from the accumulator that is under high pressure, and the pump runs to replace it.

 

I have the same problem. It is not after the car has been turned off. It is a very intermitent problem, but every time it happens it is while I am applying the brakes. I have only noticed it when I am not moving, usually right after I start the car or right before I turn it off (might always be in park?). I am not applying the brakes hard. The problem didn't start until the car had about 20k miles on it, so it is definitely a new noise... not one of the many normal ones. I agree completely with previous descriptions... it's a chirping sound... like extremely short bursts from the horn.

I'm almost out of my warranty and the dealer is telling me there is no known issue like I am describing and (of course) they can't duplicate it. The funny thing is, a friend of mine also has a prius that is doing the exact same thing. Mine is an '04 and his is either an '04 or '03. It's kind of hard to believe that I find people describing my issue exactly here... and have a friend with the same issue... yet Toyota has never heard of the problem?

Any advice and/or further info on this topic would be appreciated.

Thanks

 

<div class='quotetop'>QUOTE(eupher @ Apr 14 2006, 12:01 PM) [snapback]239718[/snapback]</div>

Well, to be sure that it is the horn, you could disconnect one of them to change the horn's sound. That way, when the short "chirp" happens, it should also change its sound if it is indeed the horn. I would suggest disconnecting both horns except that would be a safety problem. The wire to each horn has a locking connector where you have to press the tab on the side to unlock it. For instructions on how to get to the horns see: http://www.vfaq.net/mods/Horns.html .

- Tom

 

<div class='quotetop'>QUOTE(Tom_06 @ Apr 14 2006, 11:17 AM) [snapback]239730[/snapback]</div>

Unfortunately that won't work in my case because the problem is so intermitent. Sometimes it happens several times in a week, and others it goes months without happening. It hasn't happened on my car since February. If it happens regalarly again, then I'll try your suggestion. In the meantime, I'm left wondering what the problem is and if it will lead to some sort of failure after I'm out of warranty.

 

This low-decibel 'honking' happened to me very recently while on a weeklong trip to the mountains. Never happened prior to the trip, and hasn't happened since we returned. I had read about this before, so I knew it wasn't the first time it had happened to someone, but it still had me and my husband saying "what the ?" every time.

I attributed it to the unusually (to us and the car) cold temps. Temperatures while we were operating the car were between 15-20 degrees F. Under normal day-to-day operations at home the temps are between 45-80 degrees F. Car honked when it was started, and every few seconds when I applied the brakes, whether I was slowing to a stop or stopped. Very faint honk, but definitely there. Like I mentioned, I haven't heard the 'honk' since we returned to the warmer temps.

 

I am starting to hear the beep. Has anyone come up with an update of what might be causing this.

Thank you.

 

<div class='quotetop'>QUOTE(Howard @ Oct 10 2006, 10:28 AM) [snapback]330566[/snapback]</div>

Ok now i'm hearing the beep. This is very wierd. Happens when I start and hold the brake. Also if I put it in Reverse, never know when its going to happen. My friend was in the car with me and also heard the beep,, just confiming i'm not going nuts.

 

I too have noticed this in my 2009 Prius. Very intermittent and yes, it sounds as if the horn is barely activated, just enough to make a sound for a fraction of a second. If I could put it into text it would sound something like a very short, "humph". And it sounds nothing like the various noises after parking and turning the Prius off.