I stand corrected. I just tested it, and it only includes time in accessory mode or engine on. If the car is completely off, the trip time stops.I'm pretty sure that the trip time on my 2015 Edge is only the time the engine, or at least when the car is in "accessory mode."
I'm not sure how useful it would be if it just continually counted since the last time you field up, but then again, I'm sure someone would want to know that info.
Sponsored