DIY: Inverter Pump Replacement (10-15 Prius)

Thanks for posting about your experience.

How about a photo of the original vs. Aisin replacement coolant pump? Any differences in appearance?
What was the Aisin pump price from RockAuto?

 

I found your notes helpful as I just replaced my Inverter Cooling Pump on my 2010 Prius.

4 hours. I would estimate 2 hours to do it again - but such is the first time you do something.

Helps (almost impossible without) to have a helper for certain things.

After removing inverter mounting bolts and blocking up the inverter (to the rear) You need to remove the one bolt facing up from above and the hose that goes to the pump outlet (Port facing straight up - or axially).
Getting the factory el cheapo hose clamps off can be a major challenge. Large needle nose vice grips are very helpful.
I found it easier with the pump loose so I could vary the angle on the hose clamp. (Took out all 3 bolts. One from above, two from below).

You will need to bend the bracket from below to get the pump out the bottom. You'll need to compress and move the radiator hose as well.
It's tight but doable. Get the vehicle as high as practical. I used ramps and it was tight but doable.

Connector to pump maybe quite stubborn to get off (plastic hardened). I took the next connector back off and left pigtail on pump.
Much easier to do on bench once I get pump out.

Start reinstall by putting in the single bolt from above to locate the pump. Do not tighten all the way down.

The bracket that mounts to pump and provides a nut for the two bolts that mount from the bottom is a real bear.
If I had to do it over, I would have tied wrapped it to the pump, mounted the pump, and then removed each tie wrap in turn and replaced with bolts.

I fiddled with the bracket for 90 minutes before using a magnet to hold it in place from above (held by a helper). I could then hold the bracket down from below as I threaded bolts into the bracket. What a goofy design. I think Toyota hired some ex-GM Engine Engineer for this one

Easier than removing the Inverter ? Probably a wash the first time. If I ever had to do it again, this method will be faster.

Hope this helps,
Boomer

 

I had some noise which sounded as if the inverter pump was going bad. Purchased the Aisin from Rock Auto, as well as an Aisin engine water pump, as the car has 160k. Installed both today using the 2x4 inverter tilt up method, but missed connecting the inverter water pump bulkhead connector. Tried to start the car, but was presented with the red triangle of death. Turned the car off, and realized that there was a pump connection issue. Unfortuantely, after connecting the bulkhead connector, I am still getting the red triangle. Torque OBD app indicates Inverter rpm at 500 (not the normal 3350 rpm). Anyone ever run into this? If a P1314A code is thrown for a missing pump, will the ECU stay in hybrid failure mode until the code is reset? I am also am considering the idea that I have a defective new pump.