What 32 owners told NHTSA about the 2017 Hyundai Sonata Plug-in

WHILE VEHICLE IS IN MOTION AT VARIOUS SPEEDS WITH CRUISE CONTROL ENGAGED CLIMBING UP ON HILLY OR STEEPER GRADES THE VEHICLE ACCELERATES ON THE DASH AT NEARLY 100 PERCENT POWER ACCORDING TO THE HYBRID TACHOMETER. THIS INCREASE IN POWER SURPASSES WELL OVER THE SET CRUISE SPEED. FROM WHAT I HAVE NOTICED ITS 6-10 MPH CLIMBING PAST MY SET SPEED. THERE IS ALSO A LONG DELAY IN POWER RESTORATION AFTER COASTING DOWN HILLS. I FOUND IT TO BE EXTREMELY DANGEROUS WITH THE VEHICLE AT 100 PERCENT POWER BECAUSE IT COULD CREATE A SITUATION IN WHICH YOU COULD POSSIBLY REAREND ANOTHER DRIVER OR LOSE CONTROL IN NORMAL OR ADVERSE DRIVING CONDITIONS, RESULTING IN INJURY OR LOSS OF LIFE. IN ADDITION THE ISSUE COULD LEAD TO A TRAFFIC INFRACTION. MY STATE HAS A LOT OF SPEED CAMERAS. THIS PROBLEM HAVE RESULTED FROM THE RECENT RECALL WHERE HYUNDAI INSTALLED A NEW BATTERY MANAGEMENT SYSTEM. THE VEHICLE HAS APROXIMENTLY 16400 MILES ON IT.

NHTSA ODI 11192026

TL* THE CONTACT OWNS A 2017 HYUNDAI SONATA PLUG-IN HYBRID. WHILE DRIVING APPROXIMATELY 20 MPH AND ABOVE, THE CRUISE CONTROL CAUSED THE VEHICLE TO ALMOST CRASH INTO THE PRECEDING VEHICLE. THERE WERE NO WARNING INDICATORS ILLUMINATED. THE DEALER WAS NOT CONTACTED. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. THE FAILURE WAS NOT DIAGNOSED. THE CONTACT WAS TOO SCARED TO DRIVE THE VEHICLE. THE FAILURE MILEAGE WAS 6.

NHTSA ODI 11039815