2020 Hyundai Sonata Electrical Problems

Your engine has stalled and failed to restart multiple times while stopped in traffic, leaving you stuck in the intersection while other vehicles pass. This happened more than 6 times, and you had to keep attempting to restart the engine until it finally turned over. The issue appears to be related to the EGR valve, which is a known recurring problem for this model year, with repairs typically costing around $1,600.

Your car's engine won't start even though the lights, electrical components, and remote unlock work fine. When this happens, you have to turn off the ignition and try again—sometimes it eventually starts, but other times you need a tow truck or jump start. The problem happens most often in cold weather and has been ongoing for over a year, even after getting a new battery installed. The dealership hasn't been able to reproduce the issue during service visits, but it likely involves a starting system or electrical connection that needs diagnosis.

Your car wouldn't start while parked, and several warning lights came on the dashboard. After a few attempts, the engine started and the car drove normally afterward. A mechanic diagnosed the problem as a faulty starter that needed replacement, which fixed the issue.

Your car's wiring harness under the fuse box isn't making a reliable connection, which causes the blower motor to overheat and shut down. When this happens, your cabin air won't blow and your front and rear defrost stop working. You can temporarily get the blower working again by removing the fuse box cover and tapping the 30-amp fuse, but this is just a temporary fix. The dealership may need to replace or repair the wiring harness and fuse box connections to permanently solve this issue.

Your backup camera display occasionally shows only a black screen instead of the camera feed, and this happens randomly regardless of weather conditions. The issue typically resolves itself the next time you start your vehicle. The fix will likely involve checking the camera wiring, connector, or potentially replacing the camera or its control module.

The ac blower keeps going out I looked it up and a lot of people are having the same problem my ac keep having to buy blowers and they last 1 week before they stop working and they are not cheap my blower keeps going out and my electric in my car keeps messing up when I try to put the ac up it goes up then goes down I don’t know what’s wrong but I looked it up and a lot of people have the same problem

Without warning, symptoms of the A/C blower not working first occurred a little over a month ago. The fan just stopped blowing altogether (no cold or hot air). After turning the car and the A/C system on and off several times, it began working again and that was it. This past week, the same issue occurred intermittently over 3-4 days. The A/C blower did not come on for a day, the next morning it was functioning, that evening it stopped blowing again, and this went on for several days. Research of the symptoms via YouTube and many online forums, and most importantly confirmation through visual inspection of the fuse box, confirmed that the BLOWER fuse is burning so bad it has melted the connecting port in the fuse box. Whatever the electrical malfunction, the fuse burning and melting is disrupting the connection and ultimately the A/C blower itself. In the dead of such a hot and humid summer, it has been insufferable having to ride around with such inconsistent and intermittent air conditioning.

The HVAC blower motor and related electrical components (including the fuse box, wiring harness, or control module) have malfunctioned. The system either fails to operate entirely or works only on low, with unpredictable surging airflow. These components are still installed in the vehicle and available for inspection upon request. For the past five days, my family has been driving without a functioning air conditioner in extreme Oklahoma summer heat. This is not only uncomfortable but unsafe, especially for my young child who regularly rides in the vehicle. In addition, without reliable airflow, we are unable to defog the windshield in humid conditions, which significantly reduces visibility and increases the risk of a crash. The inability to regulate cabin temperature and airflow poses a serious safety hazard. Yes, the issue has been observed by the dealership during service visits. However, Hyundai has denied goodwill repair assistance and has not formally acknowledged the defect, despite Technical Service Bulletins and numerous similar reports from other owners. Yes, the vehicle has been inspected by an authorized Hyundai dealership as part of a multi-point inspection. No warning lamps or dashboard messages appeared. However, symptoms began nearly a month ago and have persisted, including intermittent blower operation, limited airflow regardless of settings, and occasional surging. While I have not personally noticed a burning smell, I’ve found numerous reports from other 2020–2021 Sonata owners describing complete blower failure and smoke smells, often tied to fuse box or electrical issues.

My 2020 Hyundai Sonata SE (82931 miles at the time) has experienced repeated issues with the front passenger window. The window would get stuck while attempting to operate it, accompanied by a loud, crushing noise. Upon visiting the dealership, I was informed that the issue stemmed from the window regulator, which had failed internally and required replacement. Additionally, my girlfriend, who owns a 2020 Hyundai Sonata SEL with approximately 31,000 miles, is now facing the exact same problem with her vehicle’s front passenger window. After conducting research on online forums, I discovered that several other 2020 Hyundai Sonata owners are reporting similar issues with their window regulators. This suggests that the problem may not be isolated to just one or two vehicles but could point to a potential widespread defect. Although this issue primarily affects the operation of the window, it could lead to safety risks if the window gets stuck in an open position, exposing occupants to potential theft, weather elements, or other hazards. I am requesting the NHTSA investigate this matter to determine if the window regulator failure in 2020 Hyundai Sonata models is a systemic defect that warrants further action, such as a recall or manufacturer response. I am happy to provide additional information or documentation, such as repair invoices, dealership statements, or records of the issue. Thank you for addressing this concern.

My Passenger window fell down and will not go up, It is available for inspection upon request. Safety Risk is that the window is being help up by tape and if it falls all of a sudden while driving could break the glass and spread inside as well as cause object to fly out of the vehicle. This has not been inspected by the manufacturer or anyone No warning lamps or messages. I put my window down and then it never went back up and motor was just running and probably made it worse

Blower motor stopped working. Same issue has now happened on my 2021 Hyundai Sonata Limited. I have been waiting now three months to have my 2020 Sonata to be fixed. Hyundai technician said the wiring harness had a crack and it’s why my 2020 Sonata’s Blower motor stopped working. It’s now three months since they diagnosed and ordered the wiring harness but supposedly it’s still on back order and I’m left with a hot car this entire summer and possibly a cold car come this winter. Now it looks like I will have the same issue with my 2021 Hyundai Sonta Limited leaving me with two cars without A/C or Heat.

Improperly seated strip fuse High Resistance Connection on the IG-2 40amp blower motor fuse receptacle causing melting of plastic fuse box components and ultimately failure of blower motor circuit and potentially loss of other circuits. Loss of blower motor leads to loss of cabin HVAC as well as loss of front windshield defrost ability during adverse driving conditions. Not only does this pose a potential electrical fire hazard, but a safety hazard due to inability to clear windshield from loss of defrost feature. Brief research finds this to be a very common problem with these vehicles. Manufacturer's recommendation is complete replacement of engine bay wiring harness. Problem begins as intermittent, but leads to total circuit failure over time if not identified.

Multi fuse controlling the A/C blower has burned out 3 times in the past year.

I was driving on the interstate when I heard a click from the back of the car. The gas gauge started to move downward as if I was losing gasoline. It eventually stopped and started moving back up, past where it was when it started decreasing. A little bit later the check engine light came on and the car started driving very sluggishly. I took the car into the Hyundai dealer and they found that the backseat was clicked out of place and a sensor was unplugged. This issue has since occurred multiple times. The back seat will pop out of place, the gas gauge will move beyond the gas that is in the tank, and finally the check engine light will come on and reduce the performance of the vehicle. The gas tank appears to be swelling and pushing up against the back seat which is causing it to pop. I had my girlfriend drive the car while I sat in the backseat and I could actually feeling something moving underneath the backseat. I have since gotten in contact with other sonata owners who have had the same thing happen with their vehicles. In other cases the backseat has exploded and flown completely off of the gas tank. I am very nervous to drive my car and think Hyundai should recall these vehicles before someone gets hurt.

Defrost doesn’t work because harness melted and blew a fuse

While driving my cars a light starting blinking and my engine light came on and the car lost power This has happened on at least 3 occasions and I had to pull over upon starting the car after a few hours all returned to normal I reported this to dealer and they could not find a problem

I took my vehicle into the dealership when it was under 12,000 miles for another issue and mentioned a problem with the headlight on the right fogging up with moisture. I was immediately told that this had to be seen with their eyes because light cost more than $1,000. It has continued for over 1 1/2 years. Early this month, I took a picture at night and in the morning. The service manager wanted to add another hoop; can you get a picture of the water in it? The water is droplets on the light, decreasing visibility on the road. Pictures are attached. There is one picture that shows the left headlight with no issue.

The AC Fan in my car quit working. Took it to a repair shop where I was told that the AC Blower Motor went bad. The blower motor was drawing too much amps and caused the blower motor fuse to melt into the wiring harness for the blower motor along with melting several other fuses nearby including the fuse box. The cost to repair this correctly fixing and addressing all parts damaged was $5000. Because my vehicle is out of warranty due to mileage I contacted Hyundai who stated that I had to go and pay another diagnostic fee at a Hyundai Dealership to have them look at it. They continued to tell me that the vehicle was out of warranty but would not assist in providing information to get the issue resolved at no cost to me.

I first begin having an issue with the idle speed. It would jump up to 1,500 RPM, which is twice the normal 750 RPM level It started almost from the very beginning when I purchased this car new in early 2020. I mentioned it at first oil change at dealer at 3,500 miles. I was told it was normal. In the beginning it would come and go. Sometimes not happening for weeks in-between episodes. Then it started to have the check engine light come on after it would happen and stay on. I took it back while light was still on and they kept the car for several days. Said it was the EPV valve and replaced it. Car operated fine for a few days then started up again. It also started to idle up and down from 1500 down to 500 in a rapid succession. I was able to get it to stop sometimes by turning engine off and them back on. Again I contacted dealership and took car back in. They gave me a loaner car and kept my car for over a month. This time they replaced the computer they told me. I did not have car for more than a week before it started doing it again. It has gradually gotten worse and happens more often now. It has also started to have the Forward Collision Avoidance warning come on in addition to check engine light as well. Just this week it actually just died on me while driving and forced me to pull to side of road. Turn off the engine and restart the engine. This happen 3 times in succession. Dealership does not seem to have any idea on what is going on and have been not very helpful. 3 week wait to get an appointment to bring in and no loaner cars available. This problem with the 2020 vehicle is very dangerous. It can idle up at anytime and car will lurch, requiring forceful brakeing . Car dying while driving and losing power as well.

Driving, car started making a weird sound followed by a warning light on dashboard with dinging sound to correlate... car became difficult to gas, vehicle motion was lagging where I just knew I had to pull over Bc this car was going to literally stop began to slowly (Bc that’s all car would allow) to proceed forward and I was forced to come to a haunt as I pulled onto side of highway. I then could no longer move it. Turned car off for minute then returned to try to start again, car would not accelerate at all nor turn on fully.. I was forced to wait hour to get a tow... took to shop, no problem such was found , car started & ran again ... this is 3 days later the car again continued the same exact pattern & I was unable to drive any further and forced to once again to get tow. This has to be something of bearings with engine, this car mode is not on list but IT certainly is an issue that I believe is related & should be rectified by Hyundai.

THE VEHICLE'S FUEL GAUGE (TYPE C) DOES NOT ACCURATELY ADJUST FOR CHANGES IN THE AMOUNT OF GAS IN A TIMELY MANNER. IT NORMALLY TAKES 2-3 DAYS FOR THE GAUGE TO MOVE TO FULL TANK EVEN THOUGH IT IS FULL. SAME PROBLEM FROM 1/4 TO 1/2 TANK, ETC. FOR EXAMPLE, I NOTICED THE PANEL SAID I HAD 11 MILES TO EMPTY ON FRIDAY. THE GAS GAUGE SHOWED OTHERWISE. I WASN'T NEAR MY USUAL FILL STATION, SO I PUT 5 GALLONS OF GAS IN THE CAR. IT IS NOW WEDNESDAY (5 DAYS LATER). THE GAS GAUGE MOVED SLIGHTLY YESTERDAY TO ALMOST 1/4 TANK, BUT THE FUEL TANK WARNING WENT FROM 11 TO 0 MILES LEFT TO EMPTY (SEE ATTACHMENT). I DROVE ON THE HIGHWAY EACH DAY AND IN THE CITY. I PURCHASED THIS CAR JULY 2020 WITH A FULL TANK. THIS PROBLEM BECAME EVIDENT IN AUG 2020. AFTER REFILLING THE TANK, THE READER SHOWED 111 MILES TO EMPTY. I INFORMED HYUNDAI AGENT OF THE ISSUE, WHO HAD NO IDEA WHY THIS WAS HAPPENING. THE GUAGE AND FUEL TANK READER FINALLY ADJUSTED AFTER ABOUT 3 DAYS. I HAD 449 MILES ON THE CAR AT THAT TIME. I NOW HAVE OVER 4,000 WITH SAME PROBLEM. APPARENTLY, SOMETHING IS FAULTY, BUT I DON'T KNOW WHAT. AUTO DEALER IS BAFFLED. THIS ISSUE COULD RESULT IN A REAL FUEL SHORTAGE WHILE TRAVELING WITH NO GAS STATION NEARBY.

I OWN A 2020 HYUNDAI SONATA. I PURCHASED THE CAR ON JANUARY THIS YEAR THE MILES IN THE CAR IS 700 MILES. A MONTH AFTER THE CAR STAR GIVING ME PROBLEM WITH BREAK. SOMEHOW THE CAR APPLIES THE EMERGENCY BREAK BY ITSELF AND DOESN'T WANT TO MOVE. WHEN I DRIVE THE CAR SUDDENLY STOP BY ITSELF AND GIVING ME MESSAGE LIKE: TO MOVE THE CAR PUT YOUR SEAT BELT, LOCK ALL THE DOOR EVEN WHEN I HAVE MY SEATBELT AND DOORS ARE LOCK THE CAR DO THAT WHEN EVER THE LESS I EXPECTED. I TOOK THE CAR THREE TIME FOR REPAIR AND UPDATE AND THE CAR GIVE ME THE SAME PROBLEM. THE DEALER GAVE ME A LOANER ANOTHER 2020 SONATA AND HAVE THE SAME PROBLEM. THIS IS A VERY DANGEROUS ISSUES BECAUSE IF IS RAINY OR SNOWING. THE DEALER DOESN'T FIND ANYTHING WRONG WITH THE CAR WHEN THEY DRIVE THE CAR. I TOLD THEM THAT HAPPEN WHEN THE LEES EXPECTED

TL* THE CONTACT OWNS A 2020 HYUNDAI SONATA. THE CONTACT STATED THAT WHILE DRIVING AT VARIOUS SPEEDS, THE PASSENGER'S SIDE BLIND SPOT DETECTION SYSTEM FAILED TO ACTIVATE. THE CONTACT ALSO STATED THAT THE FORWARD COLLISION WARNING LIGHT INTERMITTENTLY ACTIVATED WHILE STOPPED AT A RED LIGHT. THE CONTACT STATED THE REAR BRAKE ASSIST ACTIVATED INTERMITTENTLY ON SEVERAL OCCASIONS. THE VEHICLE WAS TAKEN TO NASSIEF HYUNDAI LOCATED AT 1059 OH-46 NORTH, JEFFERSON, OH 44047, AND PRESTON HYUNDAI OF SHARON LOCATED AT 1251 E STATE ST, SHARON, PA 16146, WHERE THE MECHANICS WERE UNABLE TO DUPLICATE FAILURE. THE VEHICLE HAD NOT BEEN DIAGNOSED NOR REPAIRED AS OF YET. THE MANUFACTURER HAD NOT BEEN INFORMED OF FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 623. *BF *TR

TL* THE CONTACT OWNS A 2020 HYUNDAI SONATA. THE CONTACT STATED THAT WHILE DRIVING AT APPROXIMATELY 55 MPH, THE VEHICLE SHIFTED INTO SAFE MODE AND LOST MOTIVE POWER. THE VEHICLE WAS TAKEN TO ST. CHARLES AUTOMOTIVE LOCATED AT 5601 VETERANS MEMORIAL PKWY, ST PETERS, MO 63376, (636)441-4481 BUT WAS NOT DIAGNOSED NOR REPAIRED. THE MANUFACTURER WAS NOT CONTACTED OR INFORMED OF THE FAILURE. THE APPROXIMATE FAILURE MILEAGE WAS 1,500.