Unexpected ICE start-up

I just had the ICE start on me for no apparent reason. I was driving down Santa Monica Blvd this afternoon. I was accelerating very lightly on a slight down hill and the ICE came on. I looked at the dash and it showed I was in EV and less than 1/3 the way to the power portion so that rules out accelerating too hard. At the time my speed was around 30mph. Temperature was 70 degrees so no heat or AC. The battery was at about 50%.

The only thing I can think of is that it came on because I hadn't run the ICE in a very long time. My trip B indicated that I had done 114.7 miles since the last time the ICE fired up. That's about 184 kilometers but I know that it is supposed to fire at 200 kilometers (about 124 miles). I just wondered if anyone else had seen the ICE firing up earlier than 200 kilometers?

After the warm-up cycle was done I finished my journey EV only and after grabbing a charge in Santa Monica I drove all the way home without the ICE coming on.

 

I was at about 30mph accelerating up to 35mph. The guess gage said I had 5.3 miles left from a wall charge range of 10.8 so about 50%.

 

At least the Prime Is not going to start as easily ad the PIP. I hate when mine starts when I just accelerate a little hard.

 

I tried again and this time the ICE came on at 116.3 miles so it seems like the 124 miles between ICE start-ups is just approximate. This time I was just pulling out of my garage with an almost full charge. The reported range was 10 miles and when the battery is full it normal shows 10.6 miles so I was close to full but still had a little headroom. It is up-hill from the garage to the street but nothing that would cause the ICE to come on and I was being very gentle on the accelerator at the time.

Noel