2021 Hyundai Sonata Owner Complaints

SEEMS TO BE AN ISSUE WITH THE WIRELESS APPLE CAR PLAY. REGARDLESS IF THE VEHICLE IS IN MOTION OR NOT IT LOSES CONNECTIVITY. WHILE DRIVING THIS CAUSE YOU TO TAKE YOUR EYES OFF THE ROAD AS MESSAGES APPEAR ON THEIR INFOTAINMENT SYSTEM. CALLS ARE DROPPED, NAVIGATION STOPS SO WHILE YOU ARE LOOKING AT THE MESSAGES YOU'RE NOT PAYING ATTENTION TO THE ROAD. APPLE IS AWARE BUT HAS NOT RESOLVED IT. HYUNDAI IS AWARE BUT HAVE NOT RESOLVED IT. THE INTERNET IS LOADED WITH ISSUES FOR THIS SITUATION. NOT SURE IF THIS IS SOMETHING YOU CAN ASSIST WITH BUT I'M ASSUMING AT SOME POINT THEIR WILL BE ACCIDENTS BECAUSE WHEN THIS HAPPENS YOU CAN'T USE THE HANDS FREE OPTION AS IT ALSO STOPS WORKING.

4/2/2021

Excessive wind noise is coming from the driver side window when speeds are over 55mph+. A lot of other owners on the forums are experiencing the same problem.

6/7/2021

The contact owns a 2021 Hyundai Sonata. The contact stated that while the vehicle was at an independent mechanic for an oil change, the mechanic diagnosed the vehicle with transmission fluid leaking from the engine. The mechanic informed the contact that the transmission fluid leakage was flammable. The dealer was made aware of the failure but informed the contact that they were backed up with other vehicles and could not diagnose the vehicle for approximately three weeks. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was opened. The failure mileage was 5,600.

12/2/2021

Since we purchased this brand new vehicle, we have had in the dealership service department at a minimum of 5 times for same issue. The vehicle accelerates while stopped at a light so we have to put it in neutral to keep it from accelerating. Once we take out of Neutral and release the break, the vehicle accelerates rapidly without stepping on the gas pedal. The computer system always comes on warning that we need to take to dealership because there are engine problems. Then it goes off and comes on again. We have contacted Hyundai to file a complaint and it has gone no where. We have taken it to Hyundai dealership in Tucson and they keep replacing parts per Hyundai manufacturer service tech reps. per same Egr codes. We are taking the vehicle to the dealership again today 9/22/22 because it started again around 9/1/22 and we have been waiting for a loaner car again from Dealership for same problems. Meawhile, being forced to drive it due to only owning 1vehicle. Hyundai Manufacturer has continued to have dealership change out parts and this keeps happening. The vehicle has just over 25K miles on it to date. The first time we had it in the dealership for this problem was on 4/6/22. We have almost rearended several vehicles and are scared to death to drive this vehicle. It is a safety hazard. We purchased the 2021 Sonata vehicle brand new on 11/24/21 along with the lifetime parts and labor warranty. It had 15 miles on it. We also traded our 2018 Hyundai ELantra. We paid off the 2021 Sonata completely in 2021. The total cost of this transaction was $34,294.74.We have also followed all the Maintenance requirements. It is urgent that this complaint is investigated as soon as possible and Hyundai Manufacturer take responsibility now before someone gets killed. The vehicle is obviously a dangerous manufactured vehicle.

9/22/2022

My transmission went bad on my new car. Didn’t have my car for 4 month August 12 2021

7/29/2022

The contact owns a 2021 Hyundai Sonata. The contact stated that while driving at an undisclosed speed, the vehicle made abnormally loud sounds. The vehicle was taken to the dealer where it was diagnosed that the transmission needed to be replaced. The dealer informed the contact that they were awaiting approval from the manufacturer to perform the repair. The vehicle was not repaired and remained at the dealer. The manufacturer was made aware of the failure. Upon investigation, the contact related the failure to Manufacturer Recall Number: 236 (Power Train) included with the VIN; however, he had not yet received notification. The failure mileage was approximately 28,000.

10/11/2022

UNKNOWN

10/8/2022

After 9 months of ownership, on at least five (5) instances, the car has the following things happen at the same time: 1) all warning lights on the dashboard activate, 2) the battery discharge warning light activates, a loss of power steering, no speedometer, no cameras (rear or front), no AC, and all the safety functions are disabled including but not limited to: Forward Collision Warning, Parking Collision Warning, Automatic Emergency Braking, Lane Departure Warning, Rear Cross Traffic Warning. Yes, the car is available for inspection upon request. Safety is at risk by the loss of power steering and the deactivation of all safety functions. After each instance, the car has gone back to the manufacturer's dealer for inspection, they believed it might be an electrical issue after scanning for fault codes, but after 5 times, the dealer has not yet diagnosed the issue.

3/14/2023

UNKNOWN

10/8/2022

Oct 12: Engine stalled exiting I95 in Kittery Maine. Engine light flashed but did not stay on. Was able to get to safe place but car would not go more than 15mph. Hampton Huyndai reported mis-fire but stated it cleared on its own. Oct 17th: Engine stalled on highway ramp to I495, nearly causing me to be rear ended by other vehicles. Car would not go more than 15 mph. Engine light stayed on. Towed car to Key Salem Hyundai, defective injectors, warrantee repair. Oct 23rd: Car stalls on I93, was able to take immediate exit and turn engine off. Engine light flashed but did not stay on. Took car in to Salem dealership on Oct 24th, no code found. Oct 25th: Car stalls again on city street. Light stays on, Salem dealership replaces cat. convrtr between Oct 26th through Nov 4th. Nov 9th: Car stalls again on city street. Light stays on, currently in Salem dealership. This is a safety issue, in two cases already this car has nearly gotten me in an accident on the highway. I am seeking arbitration for replacement. I am scared to drive this vehicle. I will have a third invoice pending this next repair.

11/10/2022

PANORAMIC SUNROOF EXPLOSION. HAPPENED ON OPEN HIGHWAY ROAD WITH NO CAR IN NEAR VICINITY OR SIGN OF ANY KIND OF DEBRIS HITTING THE VEHICLE.

3/26/2021

2021 Sonata N LINE NOT EQUIPPED WITH AUTO WIPERS WIPERS INTERMITTENTLY COME ON BY ITSELF WHILE DRIVING. IT HAS COME ON MULTIPLE TIMES WHEN USING MY TURN SIGNAL. WIPES ONCE THEN GOES OFF. HAS ALSO COME ON ONCE WITHOUT THE USE OF THE TURN SIGNAL. SWIPED 3 TO 4 TIMES AND THEN WENT OFF

10/29/2021

WE LEASE A 2021 SONATA SEL EQUIPPED WITH AIR BAG SYSTEM FEATURING AN OCS IN THE RIGHT FRONT SEAT. THE PURPOSE OF THE OCS IS TO DISABLE RIGHT PASSENGER SEAT FRONT AIR BAG WHEN IT DETECTS TA CHILD RESTRAINT SYSTEM OR SMALL CHILD IN THE RIGHT FRONT SEAT. RIGHT FRONT AIR BAG IS DISABLED TO PREVENT INJURIES TO A CHILD FROM A RIGHT FRONT AIR BAG INFLATION DURING A CRASH. MY WIFE IS ABOUT 4'10" TALL AND WEIGHS 135#. WHEN SEATED IN PASSENGER SEAT, SHE REQUIRES A CUSHION TO RAISE HER SO SHE CAN SEE OVER DASHBOARD AND OUT SIDE WINDOW. OUR SONATA IS EQUIPPED WITH MANUAL PASSENGER SEAT THAT IS RAISED TO HIGHEST POSITION. PROBLEM IS THAT WHEN SHE USES CUSHION, THE OCS LIGHT STAYS ON INDICATING THAT AIR BAGS ARE DEACTIVATED AND WOULD NOT DEPLOY IN AN ACCIDENT WHICH COULD CAUSE AN EXTREME SAFETY HAZARD TO MY WIFE. WE TOOK CAR TO DEALER SERVICE CENTER TWICE, AND WE CALLED HYUNDAI USA CUSTOMER SERVICE - BOTH SAID NOTHING COULD BE DONE. SMALL ADULTS LIKE MY WIFE SHOULD BE ABLE TO BYPASS THE OCS USING A SHUNT OR BYPASS SWITCH. WE FEED THIS IS A SERIOUS SAFETY HAZARD. EARLIER SONATA MODELS WERE RECALLED FOR THIS ISSUE.

10/7/2021

I turned on a highway and had gotten my car up to 45 mph when a deer came out of nowhere and I slammed into it hard back on January 12th. The car only suffered cosmetic damage thankfully, but the air bags did not deploy. I have since then found out that the front air bag crash sensors are in a spot where they are practically useless unless you hit something pretty high up and destroy the headlights in the process. In my opinion, this is a serious safety issue, and when I contacted Hyundai about it, all they told me was to go to the dealership for inspection. I have pictures showing that the crash sensors are located at and not where they should be, and if you open the hood, the wiring for the sensors is right in your face. I still have high anxiety knowing that if I get into another accident, they may not deploy due to their location. At least the car is still drivable and no structural damage or alignment issues are there. As you can see in the pictures the sensors are close to where the hood closes at the top support bar.

3/11/2022

I leased a 2021 Sonata, and the Car has been a nightmare. My Car has been serviced by the dealership twice for a steering wheel that will not stop making noises. I am very concerned for my safety in this Car. The Wheel becomes hard to move. Also, last year, the Car was in the shop for four months while the forward collision sign needed to be fixed. The Car stopped twice. I am terrified to drive this car; it only has 9,200 miles.

12/8/2022

My car barely has 11,000 miles and just the other day it had about 20miles left of gas but as I was driving on the road it started to feel and seem like it was about to die on me, Also the front Wipers are not well restrained with the vehicle you can tell by the way it moves when Wipers are on....Also most of the Signals be It if something is in front of me and the signal goes off BUT THERES NOTHING THERE ...ALSO WHEN IM BACKING UP SOMETIMES the car itself will Force stop as if something is in the way ...BUT AGAIN NOTHING IS THERE AT ALL ...IT HAPPENS EVERY FEW DAYS ....I JUST PURCHASED THIS CAR ..AND REALLY THINKING IT WAS WORST MISTAKE W ALL THESE ISSUES ALREADY

2/27/2023

As I was driving down the road I heard what sounded like a gunshot and glass shattering. Upon getting to my destination I found that my panoramic sunroof had shattered outward.

1/25/2023

I was driving down the highway with my mom, no cracks in any of my windows before any of this by the way. And my sunroof exploded. Huge huge explosion sound. I thought something fell but there was nothing above us.

6/11/2023

WE LEASE A 2021 SONATA SEL EQUIPPED WITH AIR BAG SYSTEM FEATURING AN OCS IN THE RIGHT FRONT SEAT. THE PURPOSE OF THE OCS IS TO DISABLE RIGHT PASSENGER SEAT FRONT AIR BAG WHEN IT DETECTS TA CHILD RESTRAINT SYSTEM OR SMALL CHILD IN THE RIGHT FRONT SEAT. RIGHT FRONT AIR BAG IS DISABLED TO PREVENT INJURIES TO A CHILD FROM A RIGHT FRONT AIR BAG INFLATION DURING A CRASH. MY WIFE IS ABOUT 4'10" TALL AND WEIGHS 135#. WHEN SEATED IN PASSENGER SEAT, SHE REQUIRES A CUSHION TO RAISE HER SO SHE CAN SEE OVER DASHBOARD AND OUT SIDE WINDOW. OUR SONATA IS EQUIPPED WITH MANUAL PASSENGER SEAT THAT IS RAISED TO HIGHEST POSITION. PROBLEM IS THAT WHEN SHE USES CUSHION, THE OCS LIGHT STAYS ON INDICATING THAT AIR BAGS ARE DEACTIVATED AND WOULD NOT DEPLOY IN AN ACCIDENT WHICH COULD CAUSE AN EXTREME SAFETY HAZARD TO MY WIFE. WE TOOK CAR TO DEALER SERVICE CENTER TWICE, AND WE CALLED HYUNDAI USA CUSTOMER SERVICE - BOTH SAID NOTHING COULD BE DONE. SMALL ADULTS LIKE MY WIFE SHOULD BE ABLE TO BYPASS THE OCS USING A SHUNT OR BYPASS SWITCH. WE FEED THIS IS A SERIOUS SAFETY HAZARD. EARLIER SONATA MODELS WERE RECALLED FOR THIS ISSUE.

10/7/2021

The driver seat motor malfunctioned when pennies got jammed iin the unprotected/exposed seat tracks. Hyundai would not cover the warranty and charged me $2000.00 for repair. After complaining to the Hyundai National customer service they would not consider my point of contention that the unproteted/exposed tracks contributed to the failure. A professional mechanic stated that a fuse should have failed before the motor malfunctioned.

11/16/2025

Since we purchased this brand new vehicle, we have had in the dealership service department at a minimum of 5 times for same issue. The vehicle accelerates while stopped at a light so we have to put it in neutral to keep it from accelerating. Once we take out of Neutral and release the break, the vehicle accelerates rapidly without stepping on the gas pedal. The computer system always comes on warning that we need to take to dealership because there are engine problems. Then it goes off and comes on again. We have contacted Hyundai to file a complaint and it has gone no where. We have taken it to Hyundai dealership in Tucson and they keep replacing parts per Hyundai manufacturer service tech reps. per same Egr codes. We are taking the vehicle to the dealership again today 9/22/22 because it started again around 9/1/22 and we have been waiting for a loaner car again from Dealership for same problems. Meawhile, being forced to drive it due to only owning 1vehicle. Hyundai Manufacturer has continued to have dealership change out parts and this keeps happening. The vehicle has just over 25K miles on it to date. The first time we had it in the dealership for this problem was on 4/6/22. We have almost rearended several vehicles and are scared to death to drive this vehicle. It is a safety hazard. We purchased the 2021 Sonata vehicle brand new on 11/24/21 along with the lifetime parts and labor warranty. It had 15 miles on it. We also traded our 2018 Hyundai ELantra. We paid off the 2021 Sonata completely in 2021. The total cost of this transaction was $34,294.74.We have also followed all the Maintenance requirements. It is urgent that this complaint is investigated as soon as possible and Hyundai Manufacturer take responsibility now before someone gets killed. The vehicle is obviously a dangerous manufactured vehicle.

9/22/2022

Vehicle began to lose power while on highway. The loss of power occurred for a few seconds, then came back. Shortly after, the RPM began changing uncontrollably. Tried shifting to manual control using paddle shifters and was able to maintain steady RPM until vehicle software switched back to automatic and RPM swung crazy again. Endangered other vehicles on road due to loss of power and fluctuations of transmission. Once parked, vehicle did not change to neutral, drive, reverse. Both manufacturer and insurance are/have reviewed vehicle and are working on a fix. No warning lights. Only indication was minor loss of power prior to incident. Loss of power was not considerable nor for a prolonged period of time.

4/25/2024

I leased a 2021 Sonata, and the Car has been a nightmare. My Car has been serviced by the dealership twice for a steering wheel that will not stop making noises. I am very concerned for my safety in this Car. The Wheel becomes hard to move. Also, last year, the Car was in the shop for four months while the forward collision sign needed to be fixed. The Car stopped twice. I am terrified to drive this car; it only has 9,200 miles.

12/8/2022

After 9 months of ownership, on at least five (5) instances, the car has the following things happen at the same time: 1) all warning lights on the dashboard activate, 2) the battery discharge warning light activates, a loss of power steering, no speedometer, no cameras (rear or front), no AC, and all the safety functions are disabled including but not limited to: Forward Collision Warning, Parking Collision Warning, Automatic Emergency Braking, Lane Departure Warning, Rear Cross Traffic Warning. Yes, the car is available for inspection upon request. Safety is at risk by the loss of power steering and the deactivation of all safety functions. After each instance, the car has gone back to the manufacturer's dealer for inspection, they believed it might be an electrical issue after scanning for fault codes, but after 5 times, the dealer has not yet diagnosed the issue.

3/14/2023

As I was driving down the road I heard what sounded like a gunshot and glass shattering. Upon getting to my destination I found that my panoramic sunroof had shattered outward.

1/25/2023

The contact owned a 2021 Hyundai Sonata. The contact stated that while driving approximately 70 MPH, the sunroof suddenly fractured. The contact stated that there was no external cause to the failure. The vehicle was taken to the dealer. The vehicle was not diagnosed nor repaired. The contact decided to trade the vehicle. The manufacturer was not made aware of the failure. The approximate failure mileage was 13,300.

3/22/2023

Vehicle in front of me stopped. Six car lengths between us. I applied brakes, nothing, I even put my left foot on top of my right foot. There was plenty of time to stop but brake peddle wouldn’t go down, Felt like it was locked. Automatic Brake Sensor didn’t work either. Still waiting for inspection from manufacturer , 3 weeks. Never had any problems prior to this, After accident my warning came on about front collision failure .

5/5/2023

Was driving in reverse out of garage and ABS brakes were applied like I hit a patch of ice stopping the car. Released when applied pressure to brake. Then while on highway going 60 miles an hour the emergency brake system went on for no reason applying pressure and red light came on the dash with a left facing arrow. System released within a few seconds but scared me and I still have to drive this car on highway.

1/29/2025

Was driving in reverse out of garage and ABS brakes were applied like I hit a patch of ice stopping the car. Released when applied pressure to brake. Then while on highway going 60 miles an hour the emergency brake system went on for no reason applying pressure and red light came on the dash with a left facing arrow. System released within a few seconds but scared me and I still have to drive this car on highway.

1/29/2025

During a front end collision the car did not auto brake and the air bags did not deploy. The car has been totaled and is currently at a dealership for insurance appraisal.

8/8/2025

The contact owns a 2021 Hyundai Sonata. The contact stated that after driving out of the garage and parking in the driveway with the engine idling and remote smart parking assist feature activated, 6 minutes later the vehicle suddenly began to slowly roll forward into the garage area making contact with a second vehicle that was parked in the garage before crashing into the back of the garage wall and stopping. During the incident, no injuries were reported, and no police report was filed. The vehicle was taken to the local dealer who was unable the duplicate the failure. The manufacturer was also notified of the failure. The approximate failure mileage was 1,400.

7/22/2021

The contact owns a 2021 Hyundai Sonata. The contact stated that while traveling at highway speeds, a tiny pebble hit his windshield which caused a minor ding on the middle of the driver’s side windshield. Over time, the ding spread from the driver’s side to the lane assist sensor located in the middle of the windshield. The contact stated that the crack spread vertically and horizontally across his windshield. He stated that the crack had obstructed his vision while driving at various speeds. The dealer was initially notified of the failure and informed him that he had to have the vehicle repaired by a recommended third party. The manufacturer had yet to be notified of the failure. The vehicle had yet to be repaired. The failure mileage was 23,000.

12/28/2021

The contact owns a 2021 Hyundai Sonata. The contact received notification of NHTSA Campaign Number: 21V00M000 (Visibility) however, the part to do the recall repair was unavailable. The dealer was made aware of the issue and confirmed that parts were not yet available. The manufacturer was made aware of the issue. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The contact had not experienced a failure. VIN tool confirms parts not available.

5/10/2022

Unknown

7/15/2022

Unknown

7/15/2022

The contact owns a 2021 Hyundai Sonata. The contact stated while driving at various speeds, he smelled an abnormally strong fuel odor inside the vehicle. There were no warning lights illuminated. The vehicle was taken to the dealer who informed the contact that they could duplicate the failure. The vehicle was then taken to a second dealer, Wayne Hyundai Parts and Service (1244 NJ-23, Wayne, NJ 07470) who could not duplicate the failure. The failure persisted. The contact stated that after driving the vehicle, his entire body had a strong fuel odor. The manufacturer was notified of the failure and referred the contact to another dealer. The vehicle was not diagnosed or repaired. The failure mileage was approximately 21,000.

9/14/2022

The contact owns a 2021 Hyundai Sonata. The contact stated while driving 65 MPH and attempting to accelerate, the vehicle failed to respond with the check engine warning light illuminated. The contact also heard a knocking sound coming from the vehicle. The contact pulled over on the side of the road and turn off and restarted the vehicle and the vehicle started operating as designed. The vehicle was taken to the dealer and the contact was informed that the transmission and engine needed to be replaced. The manufacturer was contacted but offered no assistance. A case was filed. The failure mileage was 2,700.

11/4/2022

My vehicle is trending in theft, car was leased to me from Napelton in Lansing IL sept 2022. The first attempt of theft/break in UIC area Dec 10, second attempt in west Chicago area Jan 29. Both times I just cried and shut down. With having to contact the police awaiting the report process in middle of Chicago Winter left me cold and in terrible distress! This is a new vehicle for me which ultimately has caused me so much stress, anxiety, and frustration. I tried to trade it in but because of this nationwide issue that I was not aware of until the first incident! Still the theft numbers continue to rise! I am being told my cars value has depreciated from 25k to 15k which is not fair, and if I abandon this vehicle it will fall hard in my credit and ruin my chances moving forward with another vehicle!! With no where to turn and In dyer need of a reliable vehicle as I work and university student, having to constantly repair the windows after random theft attempts is a major safety hazard and for concerns of what can happen in a worst case scenario. I really need this issue to be addressed so that I can freely live my everyday life and not worry if I am leaving class or work that my car will not be there, or if my windows will be busted. I hope reaching out can help me get this vehicle traded in at a fair value!

1/30/2023

The contact owns a 2021 Hyundai Sonata. The contact stated that while driving at an undisclosed speed, his son complained that the seat belt had tightened and locked and that he was unable to adjust the seat belt. Upon arriving at his destination, the contact stated that attempts to remove the seat belt had failed and the contact decided to cut the seat belt. The vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 26,450.

8/2/2023

The contact owns a 2021 Hyundai Sonata. The contact stated while driving 15 MPH, the contact noticed that the passenger’s side rear seat level had become elevated. The contact stated that his daughter who was seated in the child seat head had started touching the top of the sunroof. The contact became aware of a gasoline odor coming from the engine. The contact also became aware that the vehicle was consuming an abnormal amount of gasoline. There was no warning light illuminated. The vehicle was taken to the dealer however, the diagnostic test result was undisclosed. The dealer was unsure of how to service the vehicle. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 87,000. The VIN was not included.

5/23/2024

The contact owns a 2021 Hyundai Sonata. The contact stated while driving at an undisclosed speed, the vehicle lost motive power. Additionally, the Forward Collision Avoidance failed to function as intended. The contact stated that the sensor was braking prematurely. The vehicle was taken to the dealer; however, the failure was not duplicated. The contact stated while driving out of the driveway, the vehicle lost motive power. The vehicle failed to restart. The dealer was contacted and made aware of the failure. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The manufacturer was not made aware of the failure. The failure mileage was unknown.

9/19/2024

The contact owns a 2021 Hyundai Sonata. The contact stated while pulling out of a parking lot, the vehicle failed to accelerate as intended and started shaking abnormally. The check engine warning light was illuminated. The vehicle was taken to the residence. The vehicle was towed to an independent mechanic where it was diagnosed that the fuel injector needed to be replaced. The vehicle was towed to a dealer where it was diagnosed that all four fuel injectors needed to be replaced. The vehicle was repaired. The manufacturer was not notified of the failure. The failure mileage was 47,000.

3/3/2025