NHTSA Complaint #10758745 — 2013 FORD FUSION ENERGI

THE REGENERATIVE BRAKING WILL CUT OUT UNDER SPECIFIC CIRCUMSTANCES AND THE CAR WILL FEEL LIKE IT IS LURCHING FORWARD INSTEAD OF SLOWING DOWN. THE SITUATION IS: BRAKING USING ONLY REGEN BRAKES, NO FRICTION BRAKES; STEADY PEDAL PRESSURE; GOING 15-20 MPH; TURNING THE STEERING WHEEL AT LEAST 90 DEGREES LEFT OR RIGHT; DRIVING ON SMOOTH PAVEMENT. DATA I HAVE LOGGED FROM THE SOBDMC INDICATES THAT THE TRACTION MOTOR BRIEFLY REDUCES ITS NEGATIVE TORQUE WHICH CAUSES THE CAR TO SURGE FORWARD. IN ONE INSTANCE THAT I LOGGED THE NEGATIVE TORQUE SHOWS AROUND 48 FT-LBS AND THEN SUDDENLY DROPS TO ABOUT 8 FT-LBS. THE TRACTION MOTOR THEN GRADUALLY INCREASES TORQUE BACK TO THE APPROPRIATE LEVEL. IN ANOTHER INSTANCE THE NEGATIVE TORQUE SUDDENLY WENT FROM ABOUT 28 FT-LBS TO 8 FT-LBS. THE DROP IN TORQUE OCCURS IN 1/10 OF ONE SECOND PER MY LOGGED DATA. IT TAKES ABOUT 2.5-3.0 SECONDS FOR THE TRACTION MOTOR TO RETURN TO THE APPROPRIATE LEVEL OF NEGATIVE TORQUE TO STOP THE VEHICLE. THIS BEHAVIOR BEGAN OCCURRING RIGHT AFTER OUR VEHICLE WAS SERVICED BY A LOCAL FORD DEALERSHIP. THE WORK DONE BY THE FORD DEALERSHIP INCLUDED REPLACING THE 12V BATTERY & 3 RECALLS: 14S21, 15E03 & 15S14. I BELIEVE THAT THIS SERVICE IS RESPONSIBLE FOR THESE PROBLEMS, AS THIS ISSUE WAS NOT PRESENT BEFORE OUR CAR WENT TO THE DEALERSHIP.