8.6

pretty bad
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
3,254 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2020 Hyundai Sonata electrical problems

electrical problem

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2020 Hyundai Sonata Owner Comments

problem #16

Mar 272024

Sonata

  • miles

A D V E R T I S E M E N T S

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.

- Temple Terrace, FL, USA

problem #15

May 252024

Sonata

  • miles
Vechile shut down completely on the highway, engine's been replaced twice, Catalytic converter, Turbo was replaced three times, Battery oxygen sensors, timing belt all have been replaced, Along with my wireless charger and Both heaterhouses and splash guard. I recently had my vehicle SERVICED Thirty five hundred miles after NEW engine install The dealership serviced my car didn't reset my service indicator 3 weeks later, my vehicle without warning said Engine overheated, so I pulled over immediately that display went off. My actual thermostat stayed under the center line in between cold and hot. I contacted the dealership and got my vehicle into BE inspected At that time, they said my coolant level was low and both heapeer. Hoses needed to be replaced and my engine needed to be flushed and refilled. I had those services completed. I picked up my car 5/24 it was OK on 5/25 My service indicator pop back on and at that time it was counting 58 days, so even after I brought it to the dealership's attention, they failed to reset it again. So I googled how to reset the service interval and did it myself. And about thirty minutes later, I was driving my car started shaking excessively And Woodin's accelerate, over 20 miles per hour in traffic. I had to put on my hazard lights and get me and my grandson to a safe place so that I could contact the dealership regarding this matter and they stated there was nothing they could do I had to wait until Tuesday I have put in a complaint with the Better Business Bureau, as well as consumer affairs. And also the county attorney's office for. Consumer fraud. This vehicle was misrepresented at the time of sale. It has countless safety issues. I need assistance

- Avondale 1, AZ, USA

problem #14

Nov 152023

Sonata

  • miles
My car's battery dies 2 or 3 times every week. I have to enter into the the car with the manual key that is inside the key fob then hit the 12v rest button to start my car. I have been to two Hyundai dealerships and they both tell me nothing is wrong. I just picked it up a week a go and it has died twice since I picked up. I see many complaints on reddit about the same issue, even some with car dying while driving. This is a serious that Hyundai needs to figure out.

- Atlanta, GA, USA

problem #13

May 252023

Sonata

  • miles

A D V E R T I S E M E N T S

Defrost doesn-??t work because harness melted and blew a fuse

- Hillsborough , NC, USA

problem #12

Jan 072023

Sonata

  • miles
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

- Lafayette Hill, PA, USA

problem #11

Oct 012021

Sonata

  • miles
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.

- Murphysboro, IL, USA

problem #10

Sep 182022

Sonata

  • miles

A D V E R T I S E M E N T S

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.

- Cookeville, TN, USA

problem #9

Aug 182022

Sonata

  • 19,000 miles
The contact owns a 2020 Hyundai Sonata. The contact stated that while her husband was driving 75 MPH, the brake warning light appeared on the instrument panel as the vehicle began to hesitate upon depression of the accelerator pedal. The contact stated that the vehicle decelerated to 20 MPH as her husband pulled to the side of the highway and turned off the vehicle. The contact called the dealer and was given suggestions on how to correct the failure; however, none of the options worked. After some time, her husband restarted the vehicle and the vehicle resumed normal operation. The next day, the contact stated that the brake light returned upon start of the vehicle. The manufacturer was not notified of the failure. The vehicle was not repaired. The failure mileage was approximately 19,000.

- Grand Rapids, MI, USA

problem #8

Jul 252022

Sonata

  • miles
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.

- Rowlett, TX, USA

problem #7

Nov 012021

Sonata

  • 12,000 miles
The contact owns a 2020 Hyundai Sonata. The contact stated while parking the vehicle and pressing the power button, the vehicle continued running. The contact was able to turn off the vehicle by repeatedly pressing the power button. The contact stated no warning light was illuminated. The vehicle was not taken to a local dealer. The manufacturer was not informed of the failure. The failure mileage was approximately 12,000.

- Laguna Hills, CA, USA

problem #6

Jun 062021

Sonata

  • miles

A D V E R T I S E M E N T S

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.

- Islip Terrace , NY, USA

problem #5

Aug 042020

Sonata

  • 449 miles
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.

- Chesapeake, VA, USA

problem #4

Sep 262020

Sonata

  • 18,500 miles
Following a firmware update to the obc for a recall, the vehicle transmission now has a severe delay responding to driver input. The transmission in this vehicle has electronic shift with pushbuttons. Previous to the firmware update, the transmission would respond instantly to driver input from these buttons. Following the firmware update, the transmission takes two seconds to respond. This delayed action prohibits driver emergency shifting, creating severe risk of an accident. In my vehicle, I recently was almost involved in a traffic accident when the delayed response from the transmission caused my vehicle to reverse into the opposing lane of traffic as acceleration was attempted thinking the vehicle had shifted into drive. Upon entering the active opposite lane of traffic, emergency accident avoidance was prohibited by the delayed response of the vehicle shifting into 'drive' in order to move the vehicle from the opposite lane of traffic. Previous to this instance, there have been delays in vehicle shifting which have nearly caused an accident when the driver attempts to place the vehicle in 'park', but the delay causes the vehicle to move forward as the driver removes their foot from the brake, and the car moves forward toward stationary objects and people. This has been reported to Hyundai and they have not responded yet. Furthermore, other obvious firmware issues in the vehicle have been identified, one in a different safety system.

- New Port Richey, FL, USA

problem #3

Sep 102020

Sonata

  • miles
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

- Brooklyn, NY, USA

problem #2

Mar 092020

Sonata 4-cyl

  • Automatic transmission
  • 623 miles
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.

- Niles, Oh 44446, OH, USA

problem #1

Jan 072020

Sonata

  • 1,500 miles
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.

- O'fallon, MO, USA

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