Turn On The Electric??

Not really, but as Evan pointed out, there was one case where it caused problems with Toyota. Eventually Toyota agreed to replace the HV battery under warranty, but the owner had to remove his EV button and promise not to put it back in. No one knows if Toyota will be that nice next time around.

As to the technical answer to your question, EV mode is built into the U.S. version, so all you are doing is turning it on. The control system is supposed to take care of the battery; there shouldn't be any harm done using it. It does stress the battery a bit more, but not more than the design limits.

Tom

 

For what I can give to the forum, in my little town I can take some streets in EV mode until my PRIUS rest at home. In fact, given the low speed (10 mph), the car use to go in EV itself.

Last friday, car almost new (4 days from dealer), it took too long to get at home -some streets closed, come back and other street to pass-, and the last effort at home is in reverse to get the car in the garden and then to the car-roof. There were 4 bars when I shut off. But at saturday morning it was in pink 2 bars, probably the surface charge last night over-estimate bars.

I'm not very sure, but in event I didn't start that saturday morning, I'm afraid the HV battery could go really screwed...