We are a new owner. We've done a few days running EV only - enough to get our estimated EV range up to 50 after charging this morning. On the freeway - 70 mph - on the way home in EV my wife noticed that the ICE was running. As she remembers it, the energy was going from the ICE and battery to the wheels. This was only a few miles into the trip and lasted only a few miles. Fairly level west MI road. Our HV range dropped from 231 to 225.
It was around 90 degrees here today so the AC was running. Would this cause the ICE to run?
I drive EV pretty much every day with some afternoons at 100+ degrees and the AC blasting. What mode are you driving in -- Eco, Sport, or Normal (neither Eco nor Sport)? In Eco mode it's pretty easy to avoid the ICE coming on -- you can press the accelerator up to but not beyond the detent and stay in EV mode. In Normal or Sport mode the ICE will come on before the detent (basically when the power meter goes beyond the blue zone); I suspect that's what happened. Once the ICE comes on it will stay on until warmed up (5-10 minutes).