Hyundai Elantra adaptive cruise problems

Filed Sep 24, 2026 · Driver assistance · CA

Hyundai's forward collision warning light is on and won't allow me to use cruise control. I've tried cleaning the area, but still won't turn off. It did turn off for about an hour and while on the freeway using cruise control it came back on.

Filed Aug 10, 2026 · Driver assistance · FL

While driving on [XXX] north near exit [XXX] in rain, at 70 mph Adaptive Cruise Control and Lane Keeping Assistance were on. The vehicle displayed a warning that the smart systems were disabled. The vehicle then began jerking and changing lanes and speed unexpectedly. The steering wheel pulled/jerked forcefully to the left and right and I had difficulty maintaining control of the vehicle. When I attempted to brake, the brake pedal became very hard and could not press down the vehicle did not slow normally. I was able to get the vehicle onto the shoulder and shut it off. After restarting the vehicle, the problem occurred again. The vehicle was towed to Wallace Hyundai dealership in Stewart Florida and is currently being diagnosed. The cause has not yet been determined. Scared me to death. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jun 23, 2026 · Driver assistance, Transmission · AZ

Federal Safety Recall Fraud and Vehicle Endangerment Report Vehicle: 2022 Hyundai Elantra Blue Hybrid | Involved Dealerships: Earnhardt Hyundai North Scottsdale & Larry H. Miller Hyundai Peoria This complaint documents severe federal safety recall fraud and mechanical endangerment by authorized manufacturer franchise dealerships. In April 2025, Earnhardt Hyundai took physical possession of my vehicle for a federally mandated Hydraulic Electronic Control Unit (HCU) braking/cruise control safety recall. Staff verbally verified the recall was complete, but the physical invoice and subsequent written email admission from Service Drive Manager [XXX] confirmed the safety repair was completely omitted with "no excuse."To resolve this braking risk, on April 22, 2026, I brought the vehicle to Larry H. Miller Hyundai Peoria to have the uncompleted HCU safety recall corrected. Subsequently, on June 17, 2026, I returned to the Peoria facility for a warranty deck lid repair and a scheduled oil change.Upon releasing the vehicle on June 17, the Peoria service department actively jeopardized my hybrid engine integrity by installing an incorrect, out-of-spec oil fluid weight (5W30) and releasing the vehicle with a completely loose, unsealed engine oil cap. This gross negligence forced me into a dangerous 140-mile high-altitude mountain highway transit ([XXX] to Flagstaff) with a compromised engine bay, creating an immediate engine fire hazard and risk of sudden highway power failure. The loose cap and incorrect fluid were independently verified and caught on video by Milestone Auto Repair in Flagstaff.The manufacturer's franchise network is falsifying federally mandated safety recall records and releasing vehicles in life-threatening, non-compliant conditions. I'm requesting an immediate the federal safety agency investigation on both dealerships. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed May 5, 2026 · Acceleration, Transmission · 106,000 miles · GA

The Contact owns a 2020 HYUNDAI Elantra. The contact stated while operating the vehicle at an undisclosed speed, he noticed that his RPM were going back and forth while on cruise control, after removing cruise control the vehicle stayed the same. The vehicle was pulled over and restarted but the vehicle was hesitating to accelerate and noticed a issue with the gears not. The vehicle was towed to a independent mechanic but was not fully diagnosed due to the transmission driving forward when in neutral. The dealer was notified of the failure and a appointment was set for a later date. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 106,000.

Filed Apr 9, 2026 · Driver assistance · 10,308 miles · OH

The contact rented a 2025 Hyundai Elantra. The contact stated that while driving 80 MPH with the cruise control activated, the braking system failed to engage, causing the contact to manually depress the brake pedal to stop the vehicle. A dealer was contacted. The vehicle was not taken to a dealer or independent mechanic to be diagnosed or repaired. The failure had occurred three times. The manufacturer was notified of the failure and opened a case. The approximate failure mileage was 10,308.

Filed Dec 18, 2025 · Driver assistance · WA

I am reporting a safety-related defect involving the vehicle’s infotainment and forward safety systems. When this occurs, the vehicle also shows a “Check Forward Safety System” warning message. Diagnostic trouble code C162078 is triggered, indicating a front radar out of alignment. As a result, critical safety features such as Forward Collision-Avoidance Assist, Smart Cruise Control, and other radar-based driver assistance systems are disabled. This issue creates a significant safety risk because the driver is not alerted to potential forward collisions and cannot rely on active safety systems. The blank infotainment screen also prevents access to vehicle settings, warnings, and camera functions. In South Korea, this same defect has resulted in an official recall and free front radar replacement and calibration. However, in the United States, customers are not covered under a recall and are required to pay out of pocket for radar realignment or replacement, even though the issue is identical and a lot of time the issue came back 3 months later and customer have to pay out of pocket once again to fix the same issue. Many owners report receiving official recall notices in other markets, while U.S. owners must independently diagnose the issue. Dealers often state that the problem may be caused by radar misalignment after a software update or system fault. In some cases, cleaning or recalibration temporarily resolves the issue, but in other cases, full radar replacement is required. This inconsistent treatment places U.S. consumers at a financial disadvantage and allows a known safety defect to remain unresolved. I am requesting that the federal safety agency investigate this defect and require the manufacturer to issue a U.S. recall with free repair, calibration, or replacement, consistent with actions already taken in other countries.

Filed Nov 25, 2025 · Acceleration, Driver assistance · NJ

Cruise control on 55mph, car has slowed down going straight no uphill or downhill and accelerator did not work nothing blocking the accelerator. Had to pull over to a shoulder to shut engine off and on to drive. Tapping cruise control up to speed up in regulated area such as from 55 to a 65mph zone.. cruise control speed lowered. Attempting to speed up with accelerator still only slowing down. 3 times this year I had to change spark plugs within a 6 month period Error code p0302. Replaced battery alongside. Continues p0302 code. Replaced all coils and spark plugs still p0302. Climbing uphill vehicle sometimes looses power that happened twice in 2025 and twice in 2022. 3 times in 2024. That i must turn on hazards and floor the accelerator to gain speed on up hills in neighborhoods going 25 mph. I have dropped to 10 mph. I get oil change regularly. Always when due. Every few months I make sure to get a full car inspection to make sure everything is in proper working order.

Filed Nov 25, 2025 · Brakes, Driver assistance · ID

When I am using cruise control, my car will just randomly slam on its breaks. I have taken my car into the dealer multiple times, and they have written it off everytime. They have said it’s “direct sunlight” yet I can prove it’s not happening in the sunlight. It happened again today when it was cloudy. It’s also happened before the sun came up in the morning. I have even filed a case with Hyundai directly, and they said if they can’t get it to mimic it, then they can’t do anything about it. But it’s so random, sometimes it happens 50 miles from home, other times it’s 300 miles from home. Always willing to let anyone inspect my vehicle to help solve this issue. I’ve been taking it to my dealer for a full year until I found out I needed to come put it here. It’s random, it won’t happen in the same spot twice. But every time it’s done it, there is never a vehicle in front of me. My assumption is there is a defect with the adaptive cruise control. I’ve talked with Hyundai and they claim they’ve never heard of this happening to anyone, yet when I google it, there are MULTIPLE forums with people stating this exact thing is happening to them. SAFETY issue is it slams on the brakes so hard I’ll go from 80 to 65 before I can get the cruise control off. If someone is behind me when it does this, they will slam into me.when I’m dropping 15 mph quickly, that vehicle behind me will hit me like I’m a stopped object. No warning lights before it happens. This has been happening since I bought my vehicle at 0moled to now where I have 34k miles

Filed Nov 16, 2025 · Acceleration, Airbags · FL

Vehicle Information: 2014 Hyundai Elantra SE Sedan, 4-Cylinder, 6-Speed Automatic, FWD Build Location: USA-Built Version (Montgomery, AL - VIN '5NP') Ownership: Second owner, purchased Certified Pre-Owned (CPO) from the Hyundai of New Port Richey dealer (Florida) in March 2016. Vehicle is owned outright. Mileage: 128,638 Approximate Date Incident Noticed: October 1, 2025 DESCRIPTION OF CRITICAL SAFETY DEFECT & WARRANTY REJECTION I am reporting a failure of the clock spring assembly, which compromises critical safety features and poses an unreasonable risk, especially since this vehicle regularly transports passengers, including children. My VIN was rejected by the Hyundai TXXA Clock Spring Extended Warranty validator despite exhibiting the exact failures covered by the campaign. Safety Failures: Airbag (SRS): Warning light is constantly illuminated; driver-side airbag is disabled and will not deploy, endangering the driver and front passenger. Horn: Completely inoperable, eliminating a vital safety communication feature required to warn other drivers. Cruise Control: Buttons on the steering wheel are non-functional. These failures are caused by a broken electrical connection within the clock spring (which typically runs the Airbag, Horn, and Cruise Control circuits). I believe the denial is related to my vehicle being the USA-Built version (VIN '5NP'). I request that the federal safety agency investigate why this safety campaign arbitrarily excludes USA-built Elantras (but not Korean-built) experiencing the identical failure, thereby placing an unreasonable repair cost burden on owners for a critical safety component.

Filed Nov 9, 2025 · Acceleration, Driver assistance · MA

While driving in the rain, car reported "Check Forward Safety System". Error has not gone away multiple weeks later. Hyundai dealer's first reaction was "Oh yes, this happens all the time" (!!) but then refused warranty repair because car is in other than pristine condition, despite being only two years old, still under warranty, with pristine front bumper. Without this sensor, adaptive cruise control, collision warning system, and automatic emergency braking do not work.