10.0

really awful
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
0 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.

2021 Hyundai Sonata electrical problems

electrical problem

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2021 Hyundai Sonata Owner Comments (Page 1 of 2)

problem #25

Jun 102024

Sonata

  • miles

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

In June 2024, I was driving my vehicle when I started to smell burning from under the dashboard. As I continued to drive, the smell got worse, and on my way to the dealer, my air conditioner stopped working. I took my car back to the dealer for service, and several days later, I was told that my car needed a hardness connected to several components in the engine compartment. I remember while I was dropping off my car at the dealer, one of the service advisors told me that it was good. I drove to the dealer because the car could have gone on fire. It's now six months later, and they have not fixed my car. I was told they're awaiting parts from Korea to complete the fix. My concern is that this part can cause a fire. Why did Hyundai not recall these vehicles? Hyundai knows about the problem. I was told that I'm not the only one waiting; supposedly, there are 100's more customers waiting for this part.

- Las Vegas, NV, USA

problem #24

Dec 052024

Sonata

  • miles
the car randomly goes into dead or limp mode and unable to start. need to jump start it to come alive. No codes shown once its jumstarted. it has happened at random on several occasions.

- Woodbury, MN, USA

problem #23

Sep 282024

Sonata

  • miles
When the vehicle is turned off the 12v Lithium battery will die. This is a intermittent occurrence that has happened approximately 7 times since [XXX]. Today is December 12, 2024. The car is currently at All Start Hyundai dealership in Pittsburg, CA. This dealership initially denied the car had a problem because they could not duplicate it in a 24 hour period and told me "the car is operating as designed". When I insisted they check the health of the battery, the service department would not do this until they received technical advise from Hyundai headquarters (HQ). It is a multistep process to get to the battery and requires removing the back seat. When HQ advised the battery check, the service department found the battery was swollen and needs to be replaced. I have found information on chat boards and YouTube where other car owners having the same issue. Why hasn't Hyundai HQ issued a recall and replaced all the batteries" The dealership has told me there are batteries in inventory in a warehouse in Los Angeles California, yet HQ has them on hold on back order status. What and why would the battery not be available for the cars having the issue" I believe a swollen 12v Lithium battery is a safety hazard and should be recalled. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Brentwood, CA, USA

problem #22

Dec 032024

Sonata

  • miles

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

This car has two problems. 2 weeks I was driving on the highway. All the sudden the shutoff and lost all power on the car. Thank god I pulled to the side of the road safely. Turned the car off and turned it back on. The car started to run normal. I took it to mechanic. They scanned the car with their computer. Said the car has no problems. Tested the battery and all other components. No problems found. This happened again yesterday on the highway driving. Car engine shuts off again. The car has engine problems as well. But Hyundai denies to address it.

- Fairview, NJ, USA

problem #21

Sep 162024

Sonata

  • miles
The BMS module within my cars hybrid system failed causing a parasitic drain on the hybrid battery. The dealership where the work was performed would have to be contacted for pictures. The hybrid battery system swole to a dangerously inflated level and did not produce any codes for an OBD reader to pickup. This has caused the dealership to turn my car away multiple times before finally performing the in depth inspecting required to verify battery swelling. This is a known problem throughout the internet I searched "2021 hyundai sonata hybrid battery dying every day" reddit has plenty of user with the same issues. I am not aware of who has inspected my battery besides the dealership. There was no warnings at all the only reason my battery was finally looked at is because of my persistence.

- Yuma, AZ, USA

problem #20

Oct 062024

Sonata

  • miles
2021 Hyundai Sonata 59,850 miles RPM jumps to around 1,300 at zero miles on occasion. If I am stopped, at a red light or behind other stopped autos, the vehicle jumps forward when I take my foot off the brake. Because this happens quite often, I am aware of this and keep my foot on the brake until other vehicles are out of the way to avoid bumping into them. When this happens, I can cruise at 30 miles per hour without having my foot on the accelerator, I can slow down or stop by applying the brakes but the engine RPM stays at 1,300. If I stop and shut off the vehicle and restart, the operation goes back to normal but occurs again later. The Hyundai dealer has had the vehicle back 9 times but the issue continues. The first few times, they could not find an issue, I returned to the shop when this was happening and the service manager and a technician observed this condition, the EGR valve was replaced. Was OK for a bit but condition returned, the computer was then replaced. Condition continued. Brought the vehicle back and a scan was done and system -??re-learned. After a short time the condition returned. Went back to the service center and they did another scan and another re-learn. Condition returned 4-5 days later. Problem still not resolved. Have 59,850 miles on the vehicle, warranty expires at 60,00 miles. This started around July 1, Now October 5. Waiting for a loaner so the service center can drive it around until the situation occurs and they can bring it in immediately for diagnosis. This is the same issue as reported for the same year vehicle in July 2022.

- Attleboro, MA, USA

problem #19

Sep 072024

Sonata

  • miles

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

Blower motor on 2021 Hyundai Sonata SEL stopped working. Same issue happened on my 2020 Hyundai SEL and currently waiting on 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.

- Bradford, MA, USA

problem #18

Nov 102023

Sonata

  • miles
Fuse box has a defect causing the AC blower motor to intermittently not work. Appears to be the result of loose connections between the fuse box and the fuse itself. The receptacle for the fuse is clearly burnt/melting, and appears to pose as a fire hazard as a result. The car is currently in the shop for repair on this part, but won't likely be fixed for a month+. I do have photos of the damaged parts, should it be requested. The car was taken into a Hyundai dealership for repair work in November 2023, and I was told the fuse had blown but that they fixed it. I was never told about the box appearing damaged/melting at that time, or this being a common problem. It worked again till July 2024. Car was just dropped off 9/3, due to backlog of cars at dealership. The only symptom of issue was the AC blower motor would stop working at random. It would turn back on/off while driving. This seems to be due to the loose connections between fuse box and fuse.

- Callisburg, TX, USA

problem #17

Aug 272024

Sonata

  • miles
On three separate occasions over the last two months, while driving, an alert comes on that says check hybrid system then the vehicle powers off. When this happens, you lose the ability to accelerate break steer, and I have been lucky each of those three times and that I was in a situation where there was not much traffic. I am not able to drive the vehicle at this time. I have reported the problem to Hyundai and they want me to drive the vehicle to the dealership for another check of it. They have looked at it once before and have not been able to diagnose a problem. It is unsafe to drive and they are not willing to assist in getting the vehicle to the dealership without me getting it over there.

- Atlanta, GA, USA

problem #16

Mar 152024

Sonata

  • miles
The vehicle, after parking, is nonresponsive to the key fob, nor will it start. This can happen at anytime and anywhere. Dealer said "It is possible the integrated 12v battery into the hybrid battery may be faulty. No codes or tests can confirm the issue. The dealer said the key fobs tested ok." My wife works late at night in a dark area, this has happened 2 times at her place of work and we are concerned for her safety as she has to wait outside for a tow truck to tow it to the dealer. The first 3 times it occured, this issue started around march of 2024, and repeated every 30-45 days. Now it has happened 2 more times in the last week. No warning lamps or indications of problems. The windshield has distortion within the glass and is not a clear view. It is as though you are looking through the heat of a jet engine trying to focus on what is on the other side. This is a major distraction while driving, reading the heads up display in the car, reading street signs and general navigation of pedestrian and other vehicle traffic. There is no aftermarket film or materials on the windshield. The door handle on the drivers side has a cover plate over the hole where a manual key could be inserted. As a construction worker I have very strong hands and I have a difficult time removing the cover plate. The last time I removed the plate I cut my hand on the interior part of the handle as the cover plate popped off. That is how hard the plate is to remove. My wife cannot remove the cover plate on her own. This system is in place for the manual use of the hidden key inside the key fob to be able to open the door in the event of a power failure of the vehicle. which has now happened randomly 5 times.

- Vista, CA, USA

problem #15

Apr 042024

Sonata

  • miles

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

My battery has died twice, so dead that I can-??t even unlock to car with the remote. The first time I had it jumped and took it to the dealership where they were unable to find anything wrong with it and they told me if it happened again to have it towed in so they could diagnose it while the battery was dead. So that happened again and I had it towed in to the dealership in early April. It-??s now July and they still have my car and don-??t have a diagnosis yet. They have had their field engineers out to run all sorts of tests, but nothing yet. Today they told me they have 3 Sonata hybrids there with the same issue as mine.

- Garland, TX, USA

problem #14

Jun 282024

Sonata

  • miles
Randomly the car will get a message when driving starting -?? Check Hybrid system. Turn engine Off-?? and the car isn-??t able to accelerate when this happens. When you cut the engine off the car is unable to start again until it is jumped. I-??ve confirmed the battery isn-??t the issue however something with the vehicle is wrong. There are many accounts of people online dealing with the same issue.

- Houston, TX, USA

problem #13

Jun 112024

Sonata

  • miles
Driving on the freeway when we got a notice on the dash that we needed to pull over and the vehicle shut down due to a fuse, /battery issue.

- Rosenberg, TX, USA

problem #12

Jun 032024

Sonata

  • miles
My car will power off randomly, or will seem as though there is no power. I have to revert back to the manual key to enter the vehicle and hit the 12vlt reset to power it back on. This happened at least 3 times. Once while operating the vehicle, and twice while the vehicle was left parked. This is not a low battery issue as, the car will only do this occasionally, and not every time I enter and turn on the vehicle. There is no error code to follow this mishap as all power goes out and the dealer maintenance has nothing to work with.

- Irving, TX, USA

problem #11

May 212024

Sonata

  • miles
Integrated 12v battery in hybrid system keep draining out. I have to manually open the car and reset it every time in order to be able to drive.

- San Diego, CA, USA

problem #10

Mar 242024

Sonata

  • miles
The Battery dies randomly and requires the physical key to unlock the door. It is a hybrid, so it has a 12 volt battery button that jumpstarts the car. While driving the vehicle, the battery meter on the dashboard will show a near-full battery and then a near-empty battery within a few minutes. This vehicle was bought brand new from a Hyundai dealership and for the first 2 years, there wasn't an issue. The past few months, the battery issue started.

- Southaven, MS, USA

problem #9

Jan 012024

Sonata

  • miles
Infotainment center won't switch to Radio. No signal for AM/FM or Satellite. Then HVAC system stopped blowing. No defrost, won't blow heat or AC. Blower motors been tested and works, blower motor resister replaced. Everyone I talk to is saying it's an electrical, connection issue.

- Gowrie, IA, USA

problem #8

Feb 012023

Sonata

  • miles
the car keeps randomly dying (not during driving "yet") it happens at least once or twice a week of where i go to ride my car and it is completely dead, i have to unlock the door using the key fob manually and push the "Reset 12v battery button" inside the car. i have tried to have Hyundai service repair the issue or at least tell me what's wrong but no hope as they can never replicate the problem. I am seeing alot of users posting online on numerous web forms (reddit, facebook..etc) that they are having the same exact issue as me for the same exact model of my car, With also no help from the dealer on the matter. This must be a defect at some point and would greatly appreciate if NHTSA can help push this issue to the dealer

- Corona, CA, USA

problem #7

Mar 062024

Sonata

  • miles
The Battery dies randomly (like I have to open the car with they physical key to access the car dead) there isn't a pattern. I have taken it to the dealership and they can't diagnose it because they cant replicate the issue and say nothing is wrong. Sometimes the car dies while I'm INSIDE and just having lunch while the car is off.

- Lawndale, CA, USA

problem #6

Sep 302022

Sonata

  • miles
The vehicle has been turning completely off after use for over a year now. At first it would happen every now and then at the beginning and all you'd have to do was restart the car manually. Now every time the car is turned off it needs to be restarted manually now. The car will also shut itself off while you are driving. It will tell you something is wrong and then won't let you get over 15-20 MPH. If you are on a neighborhood, it's less dangerous for this to happen where you can pull over and turn off the car and restart it. But I have seen other post that they've started to malfunction on the freeway and highways before. My car is a 2021, but recently I've seen 2023 models are doing this as well. I know some people on the internet have gotten their car fixed by replacing a back logged battery. It took some people over a year to get it diagnosed correctly and 6 more months to get a new battery. I assume this is also what is wrong with my vehicle. It is in the shop right now, but we have not gotten an answer back even htough it's been there for 10 days. The car app has also indicated that the car has not been turned on since we left it there.

- San Antonio, TX, USA

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