I've owned a 2013 FFE for 8 days. Today, I took my longest round trip at 100 miles. On the trip back and after descending for a couple of miles, the battery icon during hybrid drive was completely full and the panel showed the engine on due to "acceleration and battery temp" for 8-10 miles. Eventually it went away and electric drive was used several times before getting home. How common is battery temp being an issue? As I said, I had descended for a few miles, using both coasting and brakes. The battery was full and the outside temp was 90. Was either or both the likely culprit?