2011 Toyota Prius Owners Manual - Page 197

2-1. Driving procedures n Situations in which EV-Drive Mode cannot be turned on The followings are examples of situations under which the EV-Drive Mode may not be turned on. If it cannot be turned on, a buzzer will sound and a message will be shown on the multi-information display. l The temperature of the hybrid system is high. The vehicle has been left in the sun, driven on a hill, driven at high speeds, etc. l The temperature of the hybrid system is low. The vehicle has been left in temperatures lower than about 32 °F (0 °C) for a long period of time etc. l The gasoline engine is warming up. l The hybrid battery (traction battery) is low. The remaining battery level indicated in the "Energy Monitor" display is low. (→P. 191) l Vehicle speed is high. l The accelerator pedal is depressed firmly or the vehicle is on a hill etc. l The windshield defogger is in use. n Automatic cancelation of EV-Drive Mode When driving in EV-Drive Mode, the gasoline engine may automatically restart in the following situations. When EV-Drive Mode is canceled, a buzzer will sound and the EV-Drive Mode indicator will flash and go off. l The hybrid battery (traction battery) becomes low. The remaining battery level indicated in the "Energy Monitor" display is low. (→P. 191) l Vehicle speed becomes high. l The accelerator pedal is depressed firmly or the vehicle is on a hill etc. 2 When driving 171 PRIUS_U (OM47685U) DVD