Really silly question, but when there are no arrows going from the engine icon on the display, does that mean the engine is shut off? When I am going down hill at 70 there is too much noise to hear if the engine is running. If yes, how quickly do the arrows go away when it shuts down? Thanks.
The engine is always at least spinning when you're at about 46 mph or above, though it may not be injecting fuel. When there are no arrows, it simply means that the engine is not producing any (significant) power that is being sent to either the wheels or the battery. It may still be spinning in fuel cut-off, or it might just be idling. From the stock gauges, there's no way to tell for sure whether the engine is off or not - that's one reason why some of us get a ScanGauge.
+1 This question has come up before with respect to the Gen II. I suspect that the answer remains valid for the Gen III. The ICE/Motor Generator/HV Battery/Wheel display is a simplification of the real power flows. It has been called a "mimic," though I don't know if that's a valid term in the formal sense of engineering/information display. At any rate, it is not an indication of the ICE on/off status. As a starter, the display cannot be wholly accurate as it only shows only one MG, and at times one of the MGs can be generating and the other motoring. Secondly, in a "no arrows glide" there is a small power flow from the HV battery to the MG. IIRC it's ~.75 HP which is not shown.
Thank you both for your answers. The information helps a lot. I guess I will have to live with a bit of uncertainty because I am not interested enough to get a ScanGauge. I work with and on computers all day at work and so I am content being one of the "just drive it" Prius owners.
