What is this sound?

That sound is from the 3 way coolant valve

 

... which is, of course, in the engine coolant loop.

 

It's not all aftermarket parts It seems to be just a few of them and it looks to me like it's a race to the bottom by factories that make things by tearing apart a factory Toyota pancake pump for the inverter and an aftermarket one you cannot tell by looking by cutting them in half. You can tell nothing is a mess The color of the circuit board the soldering the pump impeller the plastic etc all looks to be on par with a working device even looking carefully at the circuit board the soldering the mag drive for the impeller seems to look okay compared to a cut open factory Toyota Asian model so it must be something a factory learned how to do or something like this some process that they skip washing the board between soldering something I don't know. Bearings and things like that are not specific to the Prius there's a lot of cheap bearing manufacturers out there that makes these things just so you can get them on the car to sell it what is the point I don't really get that I'd rather spend the extra $28 just so the job is done reasonable I don't care about saving $28 and seeing the wheels fall off or they go round and round sounding like a cheese grater That's something for jackass in the videos not anything to do with mechanic work and working on things It's not even comedy It's just pure stupid but oh well.

 

Because that is what the code means in some other Toyotas

Bongo.

 

Or even some other car entirely. P1 codes are assigned by manufacturers, so the same P1 code is allowed to mean completely different things to different manufacturers, and even in different car models from the same manufacturer. Manufacturer's choice.



People get weird ideas of what a code is telling them either by using Google to look up a manufacturer's-choice code (and then not carefully eliminating the Google results that are not for exactly their car), or by using a generic scan tool that has some fortune cookies for codes built into it.

In general, if you're using a scan tool that isn't Techstream and it doesn't know exactly what car model you've got, you are best off just writing down what the code is, and ignoring anything the tool tells you it means, and looking the code up in your car's repair manual.

Toyota Service Information and Where To Find It | PriusChat

It's a little different if you get a code in one of the "SAE defined" ranges. Those are supposed to mean (roughly) the same thing in any car. On the other hand, because of that, they are often super generic. You might find some code has an SAE fortune cookie like "Drive Motor A Performance", but Toyota calls their motors MG1 and MG2, and you may still need to check a Prius repair manual to find out which one they matched up with the SAE codes for "drive motor A" or "drive motor B".

Keep in mind that even doing a search for the code on PriusChat is still dicey, because it will turn up all the posts by people who looked up their codes in Google and then posted about them here. But at least you will get a better signal-to-noise ratio searching here than you will by plain googling.