2007 Prius w/ 240,xxx miles, red triangle. Help!!

Prius


So, i filled up my tank today. After driving about 15 mins the red triangle, VSC sign, check engine light and exclamation point in a circle around a two brackets came on and on my navigation I see a red car with a red exclamation point thru it. The car is running fine. I did notice the AC would blow harder intermittently when i drive.


I took the car to autozone to get the code read and he said

P0420 is the catalytic converter code.


I checked the engine oil its up to the first dot on the dipstick. All the fluids are full. The car is running as usual. Would the red triangle come on if it was only a catalytic converter code? Should i be concerned about a gasket issue since the AC was blowing harder sometimes?

 

So, i took it to a dealer and they said I need to change my inverter water pump and get a flush. Quoted me 900 dollars. I declined and bough OE parts from their store. They charged me 60 bucks for diagnosis.

As i was leaving, all the dash lights were gone, did they reset all the lights? Will the red triangle come back again?

 

I was at E and it was blinking. I filled about 9.5 gallons.

 

Would you let a local mechanic replace the inverter pump? My local mechanic said 100 dollars. I have my own OE parts