Power Control Unit Coolant Reservoir

Inverter coolant reservoir....assuming that's what you are referring to?
Driver side....rear part of engine bay.
Coolant is same as engine coolant....and can be purchased pre-mixed at Toyota.
I just drained and filled my inverter coolant at 120,000 miles

 

Did they also point out to you that the radiator is actually two, one part for the "power control unit" and the other for the engine?
So if you decide to "block" the radiator, be careful to allow some airflow through all of it, to allow cooling to both systems.

 

Do you have the Owner's Manual? If not, you can download a pdf easy enough, google "Toyota Techinfo", first hit, click on the "manuals" Tab, and fill in the info. Where do you get the coolant: Toyota dealership parts department? Unfortunately it only comes in gallons, but get it once, you're good for a long time.

 

Under your hood there are two plastic tanks with pink fluid. The larger one, along the left side (as you face the engine), is the engine coolant, or "the radiator fluid". The second, smaller reservoir is the power control unit coolant.

These both use the same Toyota pink coolant. Don't use water or anything else.

 

I bought the coolant from ebay. Check prices on there before paying what the dealer wants.

 

Here's a link to a PDF version of a manual:
2010_Toyota_Prius_Owners_Manual.pdf - Google Drive
Download it cause I might remove it from my drive in a while.

 

For reference, when I bought at dealership parts department, it was $19.14 (Can), for 3.7 liter bottle, (one US gallon?).

(posting an exercise in frustration right now, took 5 tries)

 

How much did you pay?

 

When the car is ON, PCU uses energy from the traction battery to supply power to the electric engine. When you brake while driving, PCU converts energy from the electric engine to charge your traction battery.
PCU also charges your 12V battery so you don't need to have the petrol engine working to charge the 12V.

 

It's the "traffic control" for the electricity, between the hybrid battery in the back of the car, and the electric motors integrated into the transaxle, which is directly below mounted to the side of the regular engine.

 

Well, the Power Control Unit does a lot of things.
It converts the 200V DC from the traction battery to 540V three phase AC to start the engine.
It also uses that energy to power the car from time to time.
It converts the 540V three phase AC from MG1 to 250VDC to recharge the traction battery, when you are in "regenerate mode" and when it is deemed necessary by the HSD at other times.
It converts the 200VDC from the traction battery to 13.8VDC (nominal) to charge the 12V battery and keep the 12V system running.
It converts the 200VDC from the traction battery to 540V three phase AC to power the air conditioner cooling unit, and varies the speed and power to control that cooling unit.
It can also use the three phase AC from one MG (motor generator) to power the other one to add power to the wheels (torque enhancement).
It provides the power to MG1 and MG2 to vary their drag up to locking them to change the power routing in the "transmission", varying the "gear ratio" (no clutches or tapered pulleys are in there). This is the "eCVT" part of the Prius.

Without it the car won't work at all!

 

In other words, it's the thing with the huge orange power cables, and it gets hot.

For clarification: Most refer to this item as the inverter. I know that I changed my inverter coolant. I didn't know it was the Power Control Unit until now. :-|

 

With the recall, the report was that hard acceleration was the culprit, could precipitate a failure, some solder joints failing. This was what happened to @GrumpyCabbie I believe, he describes accelerating hard, and then everything shut down. So I do not know, maybe hard acceleration can still have impact, even with the recall being done.

 

$67.40 for three gallons

 

That's more than single gallon from a local dealership for me, and in Can dollars (post #8). Unless there's something prohibitive, you really should check locally first. Maybe one less contrail across the sky too, lol.

 

He he, y'all remember me

Yeah I was flooring the car in Power mode and was half way past a semi when the inverter failed on me and the car shut down! Thankfully the road was quiet otherwise it could have been interesting. I was late home, it was about 10pm and I was driving with enthusiasm.