2021 Hyundai Elantra Hybrid

Approximately once every 500 - 2000 miles (maybe more frequently this year), my car suddenly begins to accelerate hard. This happens even if my foot is completely off the gas pedal. Usually, before the problem becomes severe, there are a few minutes in which I suspect the car is sometimes lurching forward, or losing some ability to accelerate. Then the problem worsens til the car is almost undriveable... it speeds up, I slow it down with the brakes, I release the brakes, the car speeds up, I slow it down with the brakes again, and so on. The problem goes away right away when I turn the car off and then back on. I brought the car to the the dealer to investigate this when the car was still pretty new, but they found nothing. I did have a recall repair (software update) done that I thought was related to this, but it made no difference. The check engine light does not illuminate, and neither do any other warnings. It's very scary when it happens. When it's bad and I don't have an opportunity to pull off the road, I can shift to neutral and let the car coast to a stop at the side of the road. Or I can turn the engine off and then back on, while the car is still moving.

NHTSA ID

11772981

Incident

Oct 19, 2026

The contact owns a 2021 Hyundai Elantra Hybrid. The contact stated that while driving 60 MPH during ice and snow, the engine revved, and there was an abnormal sound coming from the Hybrid battery. While turning, the contact stated that the vehicle had unintendedly accelerated. Additionally, the tire pressure warning light was illuminated. The contact believed that the failure was related to the Hybrid battery. The vehicle was driven to the residence, where it remained parked and was not driven since. The manufacturer was notified of the failure. The failure mileage was 44,900.

NHTSA ID

11708400

Incident

Jan 1, 2026

Mileage

44,900 mi

The headlights and back lights turn off at random times when the headlights are on the automatic setting. This problem happens very frequently at night, putting my family at risk when the lights go off and cannot see what is ahead of us. In addition to a cop pulling me over for not having my lights on and he asked me if I was playing with the lights since they were going on and off and luckily the cop did not give me a ticket when I explained and he saw the problem (he advised me to get on this website and to make a report). I have reported this problem to the Hyundai dealership for the past 3 years and I don’t even think they take the time to investigate. The dealership just keeps telling me that with another update in the software is going to get fixed. But that is not the case. This is a very dangerous problem that is going to get someone killed. Need to be fixed

NHTSA ID

11672296

Incident

Jan 2, 2022

Check Hybrid System alarmed in heavy traffic and derated my car and put me in a very dangerous situation.

NHTSA ID

11671060

Incident

Jul 2, 2025

I am writing to report a serious and ongoing safety issue with my 2021 Hyundai Elantra Hybrid that remains unresolved despite multiple visits to Hyundai service centers and independent repair shops. I’ve also found numerous consumer discussions online describing nearly identical issues with the same model and newer Elantra Hybrid models, suggesting this may be part of a wider systemic defect. The core issue lies within the vehicle’s hybrid system. Shortly after a recent system/software update performed at a Hyundai dealership, a warning message began appearing at random intervals stating: “Check Hybrid System.” This typically first appears after extended driving — often around 3 hours — but once it occurs, the issue worsens if I continue to drive. Each time the warning appears, the vehicle suddenly and drastically decelerates without driver input, becoming dangerously slow and unresponsive, even while traveling at highway speeds. This creates an urgent safety risk, as I have had to maneuver off the road quickly to avoid collisions. After the initial warning, if I attempt to drive the vehicle again without sufficient downtime, the warning reappears much more frequently — sometimes within minutes. The only temporary relief is to stop using the vehicle and allow it to rest for at least six hours, after which the issue may temporarily subside. In every case, I must use the 12V battery reset button to restart the car, which I suspect may be clearing diagnostic codes before they can be properly recorded. Notably, the check engine light disappears after this reset, even if it was previously displayed. Given that the hybrid battery is located beneath the rear passenger seat, I am deeply concerned that if there is an underlying thermal or electrical issue, it could pose a serious or life-threatening risk to passengers. To date, no dealership or technician has been able to duplicate or permanently resolve the problem.

NHTSA ID

11661670

Incident

May 25, 2023

I have a safety recall is with a Rear view camera that hasn’t had a solution.

NHTSA ID

11632655

Incident

Dec 27, 2024

The Hybrid charging system fails once the vehicle is above 75 mph. After about an hour or two, the vehicle will die on the highway. This is a reoccurring issue putting our safety at risk. The dealership cannot find what the problem is. Online forums show similar issues with dealerships unable to solve the problem.

NHTSA ID

11624498

Incident

Sep 3, 2024

At around 93k miles my HECU unit apparently malfunctioned at the same time as the left front tire speed indicator. All of my safety features ABS, adaptive cruise control, lane departure, lane keeping etc do not work because of this.

NHTSA ID

11621727

Incident

Jun 28, 2024

This bulletin provides information related to the navigation and head unit software changes introduced in the 2026 2nd Navigation Map and Software Update. The changes may vary depending on vehicle type, model, and navigation system. Refer to the 2026 2nd Navigation Map and Software Update Key Improvements and Additional Improvements tables in this TSB for a list of specific changes. The software can be downloaded via Navigation Updater (NAU) and updated by USB.

Some vehicles equipped with internal combustion engines may exhibit higher-than-expected engine oil consumption. This bulletin outlines the combustion chamber cleaning procedure for vehicles diagnosed with this condition. All internal combustion engines consume some engine oil during normal operation, depending on driving conditions and mileage, and this procedure should only be performed when deemed necessary based on inspection and diagnosis of the vehicle as outlined in TSB 26-EM-015H, Engine Oil Consumption – Inspection & Repair Guidelines, or the latest revision.

Certain vehicles equipped with internal combustion engines may exhibit higher-than-expected engine oil consumption. This bulletin provides the inspection and repair procedures for vehicles exhibiting this condition. All internal combustion engines consume engine oil as part of normal engine operation. Oil consumption rates may vary based on mileage, operating conditions, driving habits, and maintenance history. Hyundai recommends following the prescribed maintenance schedule and periodically checking the engine oil level using the dipstick to maintain proper engine oil level.

The National Highway Traffic Safety Administration (NHTSA) has issued an urgent safety advisory regarding dangerous, counterfeit driver‑side airbag inflators manufactured by Jilin Province Detiannuo Automobile Safety System Co., Ltd. (DTN), that have been identified in U.S. vehicles following prior crashes, theft, or non‑certified airbag replacements. These inflators are not approved for use, may rupture during deployment, and have caused serious injuries and fatalities. Please see attached announcement, provided by NHTSA, for more details.

The National Highway Traffic Safety Administration (NHTSA) has identified the presence of substandard and dangerous driver’s-side airbag inflators manufactured by Jilin Province Detiannuo Automobile Safety System Co., Ltd. (DTN). These inflators were not supplied, approved, or authorized by the vehicle manufacturers and have primarily been found in vehicles that previously experienced a crash and underwent airbag replacement using non-genuine parts. These dangerous inflators have ruptured during deployment, posing a serious risk of injury or death due to metal fragments entering the vehicle cabin. To date, Hyundai is aware of three people who have died while driving a Hyundai vehicle with one of these substandard replacement airbag inflators that deployed in what likely would have been a survivable crash. NHTSA has issued a public advisory urging vehicle owners and service professionals to have vehicles inspected if there is reason to believe that a non-genuine replacement airbag may have been installed. Vehicles with salvage or rebuilt titles, prior airbag deployments, or unknown repair histories may present a higher risk. NHTSA strongly cautions against self-inspection by vehicle owners and recommends inspection by trained technicians.

Some 2019MY and newer vehicles equipped with a front view camera may illuminate certain warning lights and trigger DTC C272246 fault code for the front camera. In the following cases, the front camera auto-calibration range may be exceeded while driving: • If the front camera is not properly installed and is completely or partially detached. • In case of excessive changes affecting the vehicle's balance (e.g., loading excessively heavy cargo in a specific location of the vehicle, or significant under-inflation of the tires). • Specific road conditions affecting the vehicle's balance (e.g., excessive road crown) This TSB provides instructions on how to service the vehicle when the front camera related warning light(s) are triggered due to system out of calibration (DTC_C272246).