I own 2007 Prius with 109,000 miles. I notice a humming noise when I switch gears. It's not a loud noise because I can't hear it when the radio is on. Sometimes when I switch from Park to Reverse or Drive I can hear sort of a switch from the hood. It's not loud or anything it's noticeable when I don't have any music playing. I wanted to know what can these noises be?. Thank you for any input.
nah, it sounds normal to me. your shifter is electronic, so something has to close when you change gears, but i don't know how it works exactly.
There is no shifting of gears in a Prius, they are in constant mesh, and all change of torque/speed ratios happens by the computer changing the timing of electric pulses. However, there is a mechanical parking pawl to keep the car from rolling when in park, and that is moved in and out of position by a small electric motor when you shift in and out of park. The motor is a little black thing sitting on the front of the transmission. It's held in place by bolts with anti-tamper collars around them, because it's also the anti-theft strategy, given that the steering doesn't lock. -Chap
