FIXONICBefore you begin
Techstream was not used so we had to put the vehicle into Maintenance mode so that the vehicle can idle without the hybrid system interfering. Make sure not to drive the vehicle while in Maintenance mode, or else you can damage the vehicle. After the vehicle radiator fan kicks on, you want to turn on the heater to high so that the coolant can cycle through the heater core. After that, you are finish. You want to do this maintenance every 120k-150k miles. Also note, some models don't have a coolant bleeder valve, such as my 2012 Prius. I believe later year model has them, you can use that to bleed extra coolant out but its not necessary. Top coolant off to the B line. Follow this video tutorial by YouTuber NutzAboutBolts to complete the coolant replacement yourself.