• Fill Plug washer/gasket part #: 90430-18008
• CVT Drain Plug washer/gasket part #: 90430-12008
• Source
• Official Service Procedure from Toyota
• video from Car Care Nut (Toyota technician)

1. jumper between pins 4 and 13 of OBD2
1. start car.
1. P, R, D, R, D a few times
1. N, D over and over until D sticks (N doesn't show)
1. Shift to park. Keep engine running throughout
1. Disconnect jumper pins (important or idle speed might be incorrect)
1. While in Park, look at dash shift indicator correct temperature
  1. If no gear shown (it's blank), temp too low. Wait
  1. If D is solid, temp correct. Drain excess fluid
  1. If D blinking, temp too hot. Shut off engine, let cool down, try again.