Just out of interest

[WALLOP]

Does anyone know if the water pump continues to flow water through the cylinder linings when the car is running purely on electric? This is just out of interest as if it does i assume it would help to prevent hotspots forming in the cylinders especially when stationary and also allow more efficient cooling as the coolant will not be able to to get too hot and therefore be less effective when the engine kicks back in.

[flash22]

Good question

https://toyota-club.net/files/faq/18-03-20_faq_df_r4_eng.htm

about half way down

[TonyHSD]

20 minutes ago, WALLOP said:

Does anyone know if the water pump continues to flow water through the cylinder linings when the car is running purely on electric? This is just out of interest as if it does i assume it would help to prevent hotspots forming in the cylinders especially when stationary and also allow more efficient cooling as the coolant will not be able to to get too hot and therefore be less effective when the engine kicks back in.

Yes it does and this is the reason why they have an electric water pump at first place but it is not to prevent any engine damage from overheating but to provide heating into the cabin. 
The electric water pump is controlled by the ecu and can start late to continue to work after the engine shuts off. All depends on engine temperature and hvac settings and cabin heat requirements.
Perhaps in the event of coolant been at higher temperatures the pump will continue to work and circulate the coolant through the radiator and engine block until gets back to normal temperature and then shuts off , in winter will keep working to provide heat. 👌

[WALLOP]

Thanks for the replies Bob & Tony the Toyota-club.net link is certainly very detailed and a very good read if you are interested in the technical aspects of these new(ish) engines.