Which parts fail
Components named in complaints (battery, alternator, wiring, ignition, instrument cluster, infotainment).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2018 Hyundai Elantra owners, lightly cleaned up (personal details are redacted by NHTSA).
About month ago Sept the car would shut off when driving or stopping and find out it oil I had changed at the tire shop it was changed 2 n half months before that once oil changed running good low tire light ,oil light flash off and on at time well as of 10/12/2021 started do it my again so I check oil there no oil werid where oil go no leak on ground when I leave wherever I parked well went to Walmart get oil put oil in it and started driving not even more 35 miles bout sudden smoke coming from under engine then smell fire I pull over in parking lot at restaurant ran put fire out and it got worse trying grab my stuff and bf with me fire went inside car and under the car hear siren firemen coming if they hadn't gotten there when they did it almost went to the gas tank could of exploded firemen said look like electrical cause fire . …
The contact owns a 2018 Hyundai Elantra. The contact stated that while a friend was driving the vehicle at various speeds, the vehicle suddenly shut off and would not restart. The vehicle was towed to the local mechanic who was unable to determine the cause of the failure. The vehicle was restarted without any service being performed. The contact stated that the failure occurred intermittently. The cause of the failure was not yet determined. The manufacturer and local dealer were notified of the failure, but no assistance was offered. The failure mileage was 60,000.
So my 2018 Hyundai elantra has had the ignition/starter coils go bad now for the third time, the first 2 times the car was under warranty, I thought the second time it was odd to have the same problem, the car shakes violently, stalls out, and or refuses to start. But my warranty just ran out in 2023 and now of course the same problem is happening again, I took it to the dealer and they repaired it, it was very expensive, but I really thought since it was the same problem that they or Hyundai would cover this repair, of course they laughed at me so of course I paid it and hoped that Hyundai USA or the dealer, Ron Marhoffer Hyundai in Akron, Ohio would cover it after the fact but they both refuse simply stating that this problem happened after the 5 year warranty. …
Initial Fault Code: P0303 Replaced all 4 spark plugs and all 4 ignition coils. The check engine light extinguished momentarily but returned, logging P0303 and a new P0301 Replaced all 4 fuel injectors. CEL extinguished momentarily and then returned, logging P0303. Replaced the entire engine electrical harness. Concurrently, all related electrical components and connectors were meticulously cleaned with professional contact cleaner. CEL extinguished for significantly longer period of time, and then returned, re-logging P0303 and P0301. Thid suggested the ECU was "handshaking" with new components but re-logging the fault upon detecting the persistent core issue. A full compression test was performed. All cylinders reported results within specification. Using a borescope I inspected cylinder walls in piston tops. …
I am writing to formally report a safety concern regarding my 2018 Hyundai Elantra. The vehicle has experienced a failure of the heater hose/pipe, which appears to be made of plastic and connected to a metal component. This failure has resulted in a coolant leak, creating a serious risk of engine overheating. This issue is not only inconvenient but also dangerous. A sudden loss of coolant while driving can cause the engine to overheat without warning, potentially leading to engine failure, loss of vehicle control, or leaving the driver stranded in unsafe conditions. This is especially concerning while driving on busy roads or highways. Based on my experience and discussions with repair professionals, this appears to be a known issue with this model, as the part is not widely available outside of Hyundai/Kia and may indicate a design flaw. …
In regards to my 2018 Hyundai Elantra Limited currently with 47000 miles, driving and noticed the a/c temp display which also controls fan speed stopped working, display was blank. Checked all other electrical equipment inside car with no problem except that the heated seat function didn't work also.while doing an exterior inspection noticed that all lights except the headlights worked.After the interior and exterior inspection and no error codes or indicators on the dash, I had the alternator, battery and starter checked along with probe testing every fuse in the car and under the hood checked and everything was fine. The Car has been perfect up to this point which is alarming because if the headlights go out while driving at night or in the rain this is a safety problem and driving citation. My only indication of when this happens is if the a/c control display goes out. …
Financed last year (2021) at 38,000 miles, financing a vehicle i wish I knew to do research before hestitly excepting my first offer, first waring was on the test drive. The car had to be towed back to dealership because the battery was dead. In the sub-zero cold, the battery with read low and this causes electrical issues, from remote start not working to unable to open the doors. The more common and reaccuring issue that is getting worst is the lack of excellaration when taking off. Realizing this drastic difference recently, I know there is some thing happening, but I have not had much good customer service when I have brought issues to dealership and services center. Also issues with harness for the back left lights. The harness that holds the bulb keeps burning out. …
On 6/27/24 while starting my car in the morning an ABS failure light came on, various other system failure lights came on and have stayed on since that day including Cruise Control and Auto Hold. My car only had 33,250 miles on it! I purchased for an OBDII Reader hoping the failure was just a Wheel Speed Sensor. Unfortunately, the error code registered in the ECU was C240201 "Motor Failure" I brought in my car to a very reputable Auto repair shop, and for a $139 diagnosis fee, they confirmed that the ABS Motor / Pump had failed. The owner of the Repair Shop HAD NEVER seen a car of this age and such low milage have this failure previously. The estimate for repairs was over $2,000 as Hyundai is asking for $1300 + tax for just the part. I have read from on-line forums other Elantra GT 2018-2020 owners having the same failure and thought it should be reported.
This has happened a couple of times where in the middle of driving, my car automatically shuts off, I can not turn my steering wheel I can not push the brakes, everything stops working. I have to wait till my car comes to a complete stop on its own, put the car in park, turn off the ignition, turn my keys and start my car again. Then it sometimes acts like there is no power to accelerate when I'm at a full stop. RPMs go crazy, but acceleration doesn't occur. No warnings have ever come up. I received an notice about a recall, but it's for 2019 Elantra and up. Mine is a 2018, but the issues for that recall is the same thing that is happening with my car. This is DANGEROUS and can lead to serious repercussions or even death. Something needs to be done to fix this. I don't not have thousands of dollars to pay for an issue with the manufacturer.
The engine suddenly started stalling at stop sign or red lights at random times and the engine immobilizer light came on along with check engine and oil light. This was dangerous when turning left at an intersection. Car would be fine after restarting the car. Other times the ESC malfunction light would show while driving and the engine would not accelerate properly on the highway and the engine would also start jerking at times. Dealer said they could not fix it as this was an intermittent issues and they could not reproduce the issue when given for repair. Dealer and company did not agree to do a complete check and replace sensors, etc.
Electrical complaints in other Elantra years
Frequently asked questions
How common are electrical problems on the 2018 Hyundai Elantra?
NHTSA has 47 complaints about the electrical system of the 2018 Hyundai Elantra, 14% of the model year's 335 complaints. The component named most often is ignition › anti-theft › immobilizer/proximity › key/sender (2 mentions).
Is there a recall for 2018 Hyundai Elantra electrical problems?
No. NHTSA lists no electrical system recall for the 2018 Hyundai Elantra, though it has 1 recall for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2018 Hyundai Elantra electrical problems start?
Half of the complaints with a recorded mileage happened before about 30,000 miles, and 50% before 25,000 miles.
Is it dangerous?
Owners linked 2 crashes, 3 fires and 1 injury to electrical system problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.