Went to the garage tonight and heard a buzzing noise coming from the rear of the cars left side. After investgating the cause seemed to stem from the sunroof nkt being completely closed. seems i accidently left it open 1/2". if i did not notice this would my battery have been discharged by morning?
The reason I believe that was the cause is because once I started the car and closed the sunroof and shut down the car the noise stopped. The sunroof button would not close until I started the car so that is why I know the car was not turned on. I can not imagine what else it may have been. If the back hatch was not closed all the way would the car make that noise? I did open it to peek into the rear of the car trying to locate the sourse of the humming, however the noise only stopped after closing the sunroof. I do notice that if the sunroof is opened all the way when I exit the car, the dash displays the exclaimation sign in the yellow triangle until I close the sunroof
Not sure about the hatch, but I don't think so, unless the keys were in it or the lights were on... but not sure about the sunroof. If it has a warning to let you know it's open, then maybe it was the sunroof.
Are you sure it was any sort of warning, and not just one of the many normal noises the Prius makes while sitting parked? I can never remember the details, no matter how many times I read about it, but the car has certain things it does, even when off, and it makes noises. I doubt it had anything to do with your sunroof. Whatever it was in the middle of doing likely either coincidentally ended at the same time, or you interrupted the process by turning on the car (not something to worry about either).
Yesterday, for the first time since I got the car, I sat in for about 10-15 minutes after I shut it off. I, too, had read references to odd sounds... and was stunned, minute by minute, listening to the car talk to itself. If I hadn't already known it would do that, I might have been a bit freaked out.
Here's a quote from my Prius' owner's manual: Approximately five hours after the hybrid system is turned off, you may hear sound coming from under the vehicle for several minutes. This is the sound of a fuel evaporation leakage check and, it does not indicate a malfunction. I bet that by turning the car on to close the sunroof you simply interrupted this (natural, proper) function. Not a sunroof thing at all, I suspect.
I heard the humming once when I took some trash out late at night. Good to know that it's just a normal process of the car.
I think all C owners should, at least once, drive the car around for a bit until it is well and truly warmed up... then shut the car down and just sit with it for 30 minutes to get familiar with all the odd sounds that the car makes when we aren't normally around to hear them.
