Some 2003-2020 Toyota Prius vehicles may have a MIL on with DTC P0A80/P1AC000 and/or P0A7F/P1A8000 stored due to dust or debris buildup in the HV battery cooling fan and/or HV cooling filter. If the filter is clogged/dirty, do not attempt to clean it. The filter must be replaced.
Do not attempt to clean the HV battery cooling fan while it is installed. Doing so may cause dirt/dust to enter the battery case. Failure to secure the fan blades while cleaning the HV battery fan assembly may result in electronic circuit failure due to over-turning.
When the repair is done, reprogram the ECU with the latest calibration.