My Fusion hybrid, 44,000 miles, has been a great car, but a few months ago, the electrical motor began coming on less & less; now it almost never comes on, even when going downhill. Had it checked out by Ford but they had no answers. Of course, mileage has gone way down.
You might try going to a different dealer. Maybe one with techs trained to service the hybrid.
Similar thing happened on my 2010 Mercury Milan hybrid. After five trips to Ford dealer I finally got the story after talking to their mechanic for several minutes.
When I bought the car, it seems Ford failed to mention, that they put a timer in the high voltage system that restricts the amount of high voltage battery power you can get after 10 years. The mechanic was able to reset the clock to two years and then the car performed as it should, but he had to set it back to 10 years per ford’s instructions.
My milan has 90,000 miles, I was getting an average of 36mpg, but after 10 year clock started restricting high voltage power the mileage has dropped to 30.5mpg.
Mechanic said that they did this to prolong the life of the high voltage battery (HVB), because if the HVB fails the car will not run at all.
Thanks so much for your very informative letter! We’ll mull it over & maybe ask follow-up questions.
Really appreciate your input.
So how much is a new battery?