There are 4 owner-reported driver assist & adas complaints for the 2015 Hyundai Sonatain NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
Forward collision warning is frequently inaccurately sensing collision even when no other vehicles are on the road. I am now afraid to use adaptive cruise control because I fear sudden breaking especially when merging lanes.
ABS and Traction Control warning lights came on, then went out the next time I started the vehicle. They then did this a second time. On the third time, they stayed on. Brakes worked fine, and vehicle had plenty of brake fluid. Inspection at dealership revealed left rear wheel speed sensor malfunction. Research discovered that this could cause a braking problem as the issue continued. Dealership verified this is a possibility. Dealership also stated they have had a number of vehicles report this issue; doesn't seem to be related to any particular year.
I had a safety recall on my car for the Smart Junction Box. I took the car to the dealership on March 9th 2022. They updated the software that controlls the Smart Juntion Box. On March 11th 2022 at 6:45am I got in a car accident due to the automatic braking system failure. I run into a Ford F-150 at the stop light. Even the brakes at this point failed to work properly as well. I called the deslership and explained what happened to me and I was told by the technician that there is a possibility that the update of the software that runs the Smart Junction Box has impacted the Smart Cruize Control. He said there is a possibility that the Smart Cruize Control settings have been erased to default so the car needed a new settings. That was something I did not know about. My car has the option where you can choose what distance you want between your car and the car in fromt of you. It goes from one-space car to four-space cars. So according to the technician this may has been the problem.
MY SCC AN MY LDWS CAME ON AN MY RPM AN SPEEDOMETER GAUGE FLAT LINED ON MY WAY TO WORK GOING 55 TO 60 MPH I PULL OVER AS SOON AS POSSIBLE BECAUSE I WAS ON A HIGHWAY NOT PASSING ANYBODY I TURNED OFF THE CAR AN WAITED A COUPLE MINUTES THINKING IT WAS PROBABLY A GLITCH BECAUSE I JUST GOT MY ENGINE REPLACED FROM THE RECALL NOT TO LONG AGO AN WHEN I WAITED ABOUT 10 TO 15 MIN MY CAR REFUSED TO START AN I COULDN'T TAKE IT OUT OF GEAR AN HAD 5O HAVE IT TOWED TO THE DEALERSHIP
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 25, 2026