Is it normal? Weird electrical noise after parking

sounds like your coolant pump. situation normal. whats the ambient air temp?

 

no, the coolant pump moves hot coolant into a thermos to save for your next start up.sometimes they can be a bit noisy.

 

Can I say our cars just rock? Yes, they make all kinds of funny noises after shut down, with many of the noises being different depending on the weather and what accessories you may have been running while driving (AC, Defrost, temp control, etc). After shut down, the computer goes thru a series of things and saves what needs to be saved and shuts off other things. It can take up to a few minutes after parking. I noticed it makes more noises after running the AC or when the weather is really cold outside.

 

This is correct. Allow me to share what I learned after I bought my 2008. You might be old enough to remember when cars would start with a good sized puff of black smoke coming out of the exhaust at startup. This was because the engine burns fuel more effectively and efficiently when the engine is warm or hot than when it is cold. My understanding is that the Toyota engineers wanted to avoid polluting more than necessary and so had the idea to take hot coolant and put it in a thermos when the car is turned off. It sits there until you begin starting the car back up, and is sent back to the Internal combustion engine (ICE) when the start button is pushed to give the engine a little warm up. So turn the car off, and hot coolant gets pumped into the thermos. Turn the car on, and it's sent back to the engine block to warm it up for fuel efficient operation. Pretty neat when you think about it.
I understand there is another trick they pull regarding power brakes. The power brakes use vacuum pressure to magnify the power of your leg on on the brakes. Traditionally this vacuum pressure comes from an ICE, when the pistons are moving down and drawing air into the cylinder. It's an efficient solution, decades old, that gets the power assist from a process that is already happening.
Now if you just got in a Prius, powered it up and are rushing, you can go into drive and start driving. But the ICE might not have done anything to generate vacuum yet. If I recall correctly, they added an electric air pump to pull air out so vacuum pressure will be present, whether or not the gas engine has begun generating vacuum pressure. Also IIRC, the engineers have the pump start generating vacuum pressure when you open the door to a car that has been sitting for a while. That way the power brakes are already power-assisting when you hit the Start button. Pretty cool isn't it?

 

The thermos only appears on Gen2 NorthAmerica bound cars (USA and Canada). This was to get the Advanced Technology Partial Zero Emission Vehicle (AT-PZEV) certification by the California Air Resource Board (CARB). IIRC, the bladder gas tank for North American Gen2 Prius, is also why only we have these components.

Gen2 Prius made for Europe and Japan, lack both: thermos and bladder gas tank.

 

When people ask me why a Prius, this is one of the things I tell them. The car is just decades ahead.