What pump runs after prius turned off?

Its the pump to the CHRS coolant heat recovery system. It injects hot ICE coolant into a thermos when you shut the car off for storage so it can pump it back into the engine when starting for better emissions.
The thermos is right behind the drivers side headlight real low right in front of the drivers side wheel..

Pump failure on that thermos is not uncommon. I forget the code it throws.

This picture is with the drivers side headlight out the black thing with the 2 hoses is the Inverter coolant pump another very high failure part. The big silver round thing is the ICE thermos & pump

 

yes correct.

Good idea replacing the inverter pump it will get you and the CHRS pump going bad is no big deal. many just live with it. It will throw a code though.
I have been lucky have not had an issue with my CHRS pump but just replaced my inverter pump. Its easy.

By only an oem pump from the dealer after market pumps are junk. I like Olathe Toyota parts.

go to lusciousgarage.com site a premier prius repair shop in San francisco they show how to loosen up the front bumper allowing you to flex it down making it easy to remove the drivers side headlight.. I can do that job in about 5 minutes its easy.
After you remove the top edge bolts the Secret is getting to the bolt that holds the end of the bumper to the inner fender well. if you look at the tire at around 10 oclock there's a bolt in the inner fender well edge covered by a plastic fender well cover. Pop it out and peel it back youll see the 10 mm bolt. Once hat bolt is out pull the bumper away from the car briskly it will pop off its track. Now you can push the bumper down in front of the light and pull the light out after its 3 bolts are out.

Once the headlight is out it will look like my picture. You can use duckbill pliars or vise grips with some tape around the jaws and clamp the 2 hoses then take the hoses off and replace the pump and then top it off with inverter coolant which is the same stuff as ice coolant toyota LLC. Only hard part on the pump is the hoses will be fused to the old pump just stick a skinny screwdriver in the edge a little to break the hose free.

Eventually replace the inverter coolant that's easy.

Your good for another 100,000 miles!

Good Luck!

 

Yeah people say they can do that but I’m not sure how. If you learn how to push the bumper down it’s very handy.

if the car is new to you since your in there you may want to think about rebulb the 2 headlights unless you don’t have halogen it’s not a touring module is it with mags and leather and jbl stereo ?

 

If the hose clamps are facing the wrong way it can be hard to get a grip on them for a good squeeze. If yours are like that rotate the gripping part to a better position.

Getting the electrical connector out with the pump still in the vehicle can be a challenge. I had to use a small screwdriver to get it to unlatch once it was unbolted and lifted out enough to provide better access. There was a report somewhere on this site of a person who couldn't get the electrical connector to come out at all and eventually cut it off. That seems to be a rare problem though.

 

Four. The three shown for the engine cooling system, here, and the one for cooling the inverter (not shown in this drawing because that's a completely separate cooling system).