Sometimes when I start my 2021 Prius Limited, there's a quite loud quite high-pitched squeal. So jarring my first thought was some kind of anti-theft deterrence. But thinking it more likely it had something to do with the sound system, I tried turning off the audio system (which I've had set to an FM talk station) before turning off the power button, and in a half-dozen starts since I've been squeal-free. The squeal is so unpleasant I don't look forward to the next phase of testing where I'll go back to leaving the radio on when I turn off the power. One thing that puzzles me is that after purchasing the car used I'm pretty sure I left the audio on when powering down a good number of times before the squeal started. If I have to always turn off the sound system before turning off the car I will be annoyed.
Thanks bisco, I will. But no luck so far; I resumed leaving the sound system powered on on shutdown, and no squeals so far on about 4 startups. Unfortunately/fortunately.
you'd love my bolt, even if you turn the radio off before powering down, it comes on when you power up.
Not sure what that is, but it sounds like you're talking about something mechanical, while I think my sound was electronic.
Does the 2021 Prius Limited come with some kind of anti-theft deterrence? Because I got the sound again on startup, even though the sound system was off. But the driver door was open. Though I can't get it to do it again. Kinda reminds me of how my 2005 would occasionally get confused and make (quite different, not high pitched) alarm noises. Once my stepson was in the car and I locked it and when he tried to exit the back seat the alarm sounds went on and off until I got to the car.
there's no alarm beyond the horn that i'm aware of, but dealers and owners sometimes add aftermarket units
