2020 Hyundai Sonata driver assistance problems

Filed Nov 2, 2026 · Driver assistance, Electrical · UT

My 2020 Hyundai Sonata has a recurring electronic system malfunction that causes multiple dashboard warning lights to illuminate, including the Forward Collision-Avoidance Assist System warning. When this occurs, the vehicle can suddenly lose the ability to accelerate. Most recently, this happened while driving in rainy conditions, creating a serious safety hazard. The vehicle has undergone multiple unsuccessful repairs at Hyundai dealerships, including an extended four-week repair involving Hyundai's technical specialists in 2025. The same problem has now returned, and I am concerned about the vehicle's safety and reliability.

Filed Aug 26, 2026 · Brakes, Driver assistance · NC · crash

Parking malfunction. Parked, running car moved itself to reverse and backed up a driveway crossing a dirt road and hitting a fence and post. This car could have hit and severely injured anyone who was in the path while it was reversing on its own. Car was in reverse and all parking sensors were blaring when the car was found minutes later.

Filed Aug 23, 2026 · Driver assistance · AZ

The reverse camera only shows a black screen and will put drivers in danger while not being able to see behind them while reversing. This needs to be recalled and repaired. Especially in situations where a person is reversing out of a driveway onto a major/busy road. Sometimes it works, but a lot of the time it is just a black screen with the green, yellow, and red lines to indicate how far your wheel is turned. But it doesn’t allow you to actually SEE where you’re backing up into or the cars coming from either side of you while trying to back out. It’s very dangerous and it seems to a be manufacturer’s defect that needs to be addressed by the company itself, since they’re the ones who made and installed the product incorrectly.

Filed May 29, 2026 · Driver assistance · 2,000 miles · CA

The contact owns a 2020 Hyundai Sonata. The contact stated while driving at various speeds, the vehicle experienced phantom braking and nearly came to a complete stop. The contact stated that the automatic emergency braking system unexpectedly engaged while there were no roadway obstacles or vehicles near the vehicle. The vehicle was taken to the dealer, who informed the contact that they would need to verify whether the repair would be covered under the active warranty. The vehicle was not yet diagnosed or repaired. The manufacturer was not yet contacted. The failure mileage was approximately 2,000.

Filed Feb 16, 2026 · Driver assistance · NY

Rear camera doesn’t work and is just a black screen. It started out intermittent and now doesn’t work at all.

Filed Oct 30, 2025 · Driver assistance · 130,000 miles · TN

The contact owns a 2020 Hyundai Sonata. The contact stated that while reversing, the back-over prevention camera malfunctioned, and there was no image of the rear of the vehicle displayed. The contact stated that the display screen only displayed lines. The contact stated that the failure caused a visibility hazard for the driver. The vehicle was examined by an independent mechanic who determined that the camera was faulty and needed to be replaced. The vehicle was not yet repaired. The local dealer and manufacturer were not notified of the failure. The failure mileage was 130,000.

Filed Sep 12, 2025 · Driver assistance · 46,000 miles · AL

The contact owns a 2020 Hyundai Sonata. While the contact's wife was reversing, the back over prevention camera system displayed a black screen. The dealer was made aware of the failure. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The contact referenced an unknown recall with a similar failure; however, the VIN was not associated. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 46,000.

Filed Jun 3, 2025 · Driver assistance · 64,000 miles · NC

The contact owns a 2020 Hyundai Sonata. The contact stated that after shifting into reverse(R), the back over prevention camera screen temporarily displayed an image before the screen went black. The contact stated that the failure had become a recurring failure, but recently became a constant failure. The contact had not taken the vehicle to a dealer or independent mechanic to be diagnosed or repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 64,000.

Filed May 4, 2025 · Driver assistance, Electrical · TX

My 2020 Hyundai Sonata has a recurring defect in its engine or transmission, causing sudden deceleration to ~10 mph without warning, often on major highways, with warning lights (check engine, ESC, traction control, etc.) flashing seconds before the car decelerates. This forces me to swerve off busy roads, endangering me, my passengers, and other drivers. Near-misses with traffic pose an extreme safety risk, causing significant emotional distress. The car, at a Hyundai dealer since April 21, 2025, is available for the federal safety agency inspection. The issue began in January 2021, five months after purchase, with all the warning lights appearing during incidents along with rapid deceleration. The Hyundai dealer confirmed the problem in seven repair attempts (January 2021, December 2021, January 2022, November 2024, February 2025, and twice in April 2025) but never properly diagnosed or fixed it, citing no consistent diagnostic codes. Only the dealer assessed it; no inspections by Hyundai’s manufacturer, police, or insurance occurred. In November 2024, the defect recurred immediately after pickup, despite false assurances it was fixed. In February 2025, the dealer kept the car over a month with minimal communication, yet it failed again. I picked up the car on April 4, 2025, but it broke down on April 6, less than 55 hours later. I returned it April 7 and picked it up April 17, and it failed again on April 21, 2025 with the vehicle remaining at the dealer since. The dealer and Hyundai offer no solution and this dangerous issue keeps recurring. Similar the federal safety agency complaints suggest a broader issue. Rapid recurrences—hours after April 4 and four days after April 17—prove the car is unsafe and assurances of repairs are untrustworthy. I no longer trust the Sonata or Hyundai’s repairs, as the defect persists.

Filed Apr 6, 2025 · Driver assistance, Electrical · TX

My 2020 Hyundai Sonata has a recurring and dangerous defect involving sudden deceleration while driving. Without warning, the car abruptly slows to ~10 mph—often on the highway—while numerous dashboard warning lights activate. This poses an extreme safety risk to me, my passengers, and other drivers, as it forces me to maneuver off the road to avoid being hit. The issue began in January 2021, just five months after I purchased the car new. It has occurred repeatedly and unpredictably since then. I have taken the vehicle to Hyundai-authorized dealers for repair on five occasions (January 2021; December 2021; January 2022; November 2024; and February 2025), but the problem has never been properly diagnosed or fixed. In November 2024, the issue occurred immediately after I picked the car up from the dealership when they told me it was fixed and ready to drive. This most recent occurrence (February 2025) before tonight's incident on April 6, 2025, the dealer had my vehicle for over a month. During this time, communication was seldom initiated by the dealer. Now the problem recurred less than 55 hours after picking the vehicle up from the Hyundai certified dealer, who told me the issue was fixed and the car looks and runs great. Unfortunately I found myself in this dangerous situation despite the dealer's reassurances and Hyundai's involvement overseeing the repair process. The unsafe, defective Sonata is currently in my possession as I figure out next steps. Each incident is accompanied by multiple warning lights (e.g., check engine, ESC, etc.) but the dealer represents that no consistent diagnostic codes have been found. I’ve also found multiple similar complaints from other Sonata owners on the federal safety agency site, suggesting this may be a broader issue. This unresolved defect has made the vehicle unsafe to drive and caused significant emotional distress. I no longer trust the car or the assurances from Hyundai or the dealer that it is fixed.