A little help diagnosing this would be appreciated. This is NOT a joke! I have owned the car since NEW and it now has 119,000 miles on it. So I am quite familiar with noises the car routinely makes... This started about a week ago... I did not think the noise was coming from the Prius ... but now it is confirmed. I have only noticed the noise when the engine is off. For instance, pressing the power button to start, leaving the car in Park and a few seconds before the engine starts (not every time mind you) a noise lasting about 1/2 of one second. It is LOUD and sort of a "BHONK". I have also heard this noise setting at a red light. It is VERY loud. It is loud enough that others think I am Honking at them and they will honk back! Here is more to go on... I have found a way to recreate it all most every time. (Nothing is perfect) Here we go: With the car fully warmed up after driving around for say 15 minutes, slow down and stop in such a manor that the engine is off. While watching the Energy Display make sure the engine is off and adjust the brake pressure so that the battery remains supplying power to the MG's. The noise will NOT occur at this point. I have waited a full FIVE minutes and the noise did NOT occur! NOW, for the noise... Press the brake firmly. The Energy Display will show that the battery is no longer supplying power to the MG's. About 5 seconds later "The sound". Someone that has a flow chart or understands the various functionalities SHOULD be able to tell me what cycles at this point! I know this is not much to go on but it is so fast and intermittent that it is difficult to isolate. I thought at first the horn was intermittently beeping due to a computer or electrical failure but the sound is wrong. The noise is a little lower frequency than the horn. Perhaps a pump is trying to start and the impeller rubs the casing occasionally... BTW, the temperature when this happens is mid 40's to low 60's F. Thanks in advance!
perhaps your talking about the sea lion infestation? see this thread, complete description and solution in my post on page 5.
I've had my Prius for about 4 years and I'm always "hearing a new sound", or so I think. As long as I have no warning lights and the car feels right to me, I just turn up the radio and go along my merry way. The same thing has happened with every car I've ever owned. Sometimes it turns out to be mind over matter. My thoughts...
On my '08, after turning the power off I can hear a buzzing noise under the hood. I suspect it is the Hybrid system that is 'doing its thing'. Yes, the car runs great and I am still in the break-in period...closing 2K.
A followup... Perhaps it WAS an ABS component "barking" but like several other problems I have had... I post the issue here and like magic the problem goes away! It has been gone about a week now! I did nothing to it. I love these self repairing cars!
Hi Jim..., Is there any consistancy in speed when the BHONK happens? Like 7 mph ? That is the speed the regeneration kicks out and the hydraulics actuate the fricting brakes. If so, that would imply the BHONK is the brakes taking up the wear clearance (which would need to be huge) when the Hydraulics press the pads to the caliper, or the calipers are binding. If that is the case, then a caliper cleaning is in order. Look for the caliper binding mechanisms, or that if the guides and guide bushings (if the Prius has those?) are not worn or nicked. Properly lubricate the caliper guides Hobbit has a write-up on caliper maintenance on his web site.
I have this EXACT same noise, only it is a little softer. Sounds just like someone lightly bouncing thier fist on the horn to remind someone in front of them that the light has turned green and to get going! There is a service bulletin in regards to this brake noise....they call it a "squeak" but I think this is the noise they are reffering to. See the TSB section at the top of the page and look up "Brake Noise" (TSB BR001-07). When I was in for a routine inspection, I mentioned this soft "honking" noise to the service department.....they lubed the brake pedal linkage. Of course it is still there. I wil have them bleed the brakes next....then replace the ABS brake actuator assembly under warranty if neccesary. Rather aggravating little noise, isn't it?BR001-07
Well maybe, but some people buy cars and keep them in the long run, as it should be, knowing how difficult it can be to pay a new car. But maybe this car is long gone from his hands, maybe the car is not even in the road anymore, could have ended its Priii life in an accident. I doubt this person will even answer my question.
Ohhh i see, well i don't know if it's the best decision to trade a car just because of such problem, it depends though if you are able to replace the actuator yourself or not, if you can then you will save a lot of money.
agreed. but he was not a diy'er. he got quite a few years after the honking/barking started, so it wasn't worth putting the money into it.
I understand, some people just do not have time to do these things due to work, or they are not good at it [or that's what they think], or they are not interested in learning how to do it, they should. Well, it's good to know what happened to his Prius, thank you for telling. Now i wonder why he was last time online 8 years ago, i hope he is okay.
There was a honking noise that I disliked a few years ago, I looked up the TSB and asked the dealer to flash the brake ECU firmware update mentioned in it, and the noise went away. If the ECU is already at the recommended firmware version and there is still a honk, I would try the bleed procedure (the more thorough one, for when the underhood bits have been replaced). That might get some gas bubbles out of the way, and I believe the honk to be produced when a bubble squirts fluid past one of the actuator valves, working it like a saxophone reed. If that doesn't tame the noise, or it comes back too soon, actuator replacement may be indicated.
