I traded in my 2006 Prius in on a new 2013 Prius. I have had it for 3 months now and it's developed a few strange problems. 2013 Prius Problems: 1/10/13: Went out to the garage and heard something running on the vehicles. Sounded like it was coming from the rear. Entered the vehicle and it was louder coming from the back. Nothing was on in the Prius, so I started it up then turned it off and the noise disappeared. It really sounded like a pump running. 2/4/14: Turned on the front defroster to clear the windshield, after about 5 minutes I turned it off by it's button; however it would not shut off, even tried pressing the "Off " button but it still would not shut off. Finally I had to shut the car off and turned it back on and it seemed to reset itself. 2/7/13: Went out to the garage and heard something running which sounded like it was coming from under the hood. Got into the Prius and the whining sound was louder coming from the dash panel. I had driven the car earlier that morning and the battery showed it was at a full charge less one notch. When I started the car up after hearing the whining sound it was down to 1/2. After shutting the car back off the sound disappeared. 3/1/13: Returned from dinner in our Camry and parked it in the garage, when my wife and I got out of the camry she asked was something running. We both heard what sounded like a pump running with a low whining sound. I went over to the Prius and it seemed to be coming from the rear of the vehicle. I crawled under the rear of the Prius and it appeared to be coming from the gas tank area; I recorded the sound on my iPhone. To further try to pin-point the sound I removed the gas cap. Upon removing it, pressure was released and the sound stopped. I will have them addressed when I have the oil changed but was wondering if anyone else have experienced anything like this on their 2013 Prius.
I believe the noise you are hearing is the vacuum pump for the brakes. Mine does that as well sometimes. The car has its own brains...
Asked and answered here many times. You should find something like this in your manual: Approximately five hours after the engine is turned off, you may hear an electric motor sound under the luggage compartment for several minutes. It is not a malfunction. It is the sound of a pump performing a fuel evaporation leakage check. Read more: http://priuschat.com/threads/buzzing-sound-from-underneath-while-powered-off.102466/#ixzz2O7yXRgan
I must be an old fart, but it's easier for me to read the pertinent part of the car manual than to type a long, multi-paragraph question on a forum.
The noise in front. The car recognizes your key fob / open the door, and then pumps up the brakes so they are ready for you to start your car. Just my best guess!
I one time my 2012 was making odd noises and beeps, then I figured out I left the car with the keys in my pocket but never turned the car off. Very hard to arm a running car.
