i got home yesterday around 5 pm, and after 5 1/2 hours, noticed a buzzing noise from the battery area. it was 50 degrees out, so i don't think it needed cooling? anyway, i plugged it in for a minute and the sound changed, then unplugged and after a few minutes the sound shut off. never experienced this before, so long after shutting down. no sound this morning and charging now, no problem so far.
It's normal... I usually relocate my PIP after it's morning recharge has completed from the public charge station around 10:15am, my usual lunch time is from 3-4pm. Many times when I go out to the PIP around 3pm (5+ hrs after last moving the PIP) or so I hear that fan (or something that sounds like some sort of motor) running. During it's run cycle I also hear it change pitch several times till it finally turns off for good. I think you could write a book covering all the strange sounds the PIP makes before and after starting or shutting it down
First - It is a relief to hear. Second - I wish other users would be as considerate as you are in using public charging stations!
From T0yota'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.
