2010 Prius inverter overheat P0A93

Hello, wondering if anyone else has had this experience with their Gen3 Prius. Once it turned 100k miles I took it in for an inverter coolant change per the maintenance schedule. The dealer charged $109 for this and the car had absolutely no issues prior. Got the coolant changed on 7/23 and then drove it short distances in town for two weeks with no issues. Once I drove it on weekend longer road trip got a check engine light P0A93 "inverter A cooling system performance". Shortly there after started getting hybrid overheat alerts and pulled over to let it cool.

I checked the inverter coolant reservoir and it was still above full. After letting things cool, I turned it back on and listened to the water pump. Seemed to be running fine, heard it clearly with my ear up to a long screw driver, touching the pump. Noticed that the hose leading to the pump was vibrating but the return hose out of the inverted was not. Also no turbulence in the reservoir. My guess is that they didn't bleed air out of the system.

Called the dealer and told him the check engine code and service advisor goes "oh that's for air in the cooling system, sure bring it back!".
Then he calls me after I took it in and says its a problem with the water pump. $500.
me: "how do you know there's no air in the system, is there a bleeder valve somewhere?".
SA: "no way to know for sure but with these models we can be confident there's no air because the reservoir sits up high"
SA: "we hear the pump running but think there must be an issue with the impeller"
me: "ok please give me the car back"

Thoughts? Is there a way I can bleed air out of the system if they wont/don't know how?
Otherwise I was going to replace the pump DIY and take a video of the impeller if a see it rotating fine.

 

The more I thought about it the more I seemed to agree that it was the pump. I took it home and unhooked one of the return hoses and there was very little flow. Like an inch per minute. So I replaced the pump this morning and now all is well. I guess as it turns out the dealer was right. I don't know how a simple coolant changed would have caused this, seems like it was just a coincidence the pump went out two weeks later.

Anyways I've search hi and low and seems in the only one with a gen3 with a inverter pump failure. No YouTube vids, posts, and even the service advisor said its a first.

In case this happens to anyone else, the method I used:
1, remove the air cleaner assembly,
2. Disconnect negative on 12v battery
3. Remove plastic under cover and Drain coolant
4. unhook hoses from the inverter,
5. unclip low voltage wiring, leave high voltage lines in tact.
6.Release all high voltage cable management clips to provide slack.
7. Lift up the inverter and place a block of wood under it.
8. Disconnect hoses from pump (difficult, little working room.)
9. Remove 1 of 3 pump bolts from above with long extension /swivel socket.
10. Remove 2 of 3 pump bolts from below with a long extension and swivel socket. Small bracket will come loose that has the threading for these two bolts, difficult to reassemble.
11. Remove electrical connection from pump from below.
12. Remove the pump from above

Replacement was reverse of removal. Had the wife start the car up to get the pump running while I kept adding coolant. Saw lots of air bubbles until fluid level stopped dropping.

Got the oem from Amazon in 2 days
Part# G9049-47090