For vehicles with the lamps on reminder light, it comes on when the lights are in use.
Engine Heater
The engine heater, if available, can
help in cold weather conditions at or
below −18 C (0 F) for easier
starting and better fuel economy
during engine warm-up. Plug in the
engine heater at least four hours
before starting the vehicle. An
internal thermostat in the plug end
of the cord ...