Technical service bulletins are instructions a manufacturer sent its dealers about a known fault. They are not recalls and the work is usually not free, but they are the clearest signal of a problem the manufacturer already knows about.
26-01-060H TSB
Warranty Program/Extension
Certain Sonata (DN8) vehicles may exhibit a transmission oil leak at the bottom of the valve body cover due to a loose oil level plug that could potentially lead to a total failure of the automatic transmission. This bulletin provides instructions to inspect the oil level plug and transmission oil level and, if necessary, replace the automatic transmission.
26-01-060H WebDCS
Warranty Program/Extension
Certain Sonata (DN8) vehicles may exhibit a transmission oil leak at the bottom of the valve body cover due to a loose oil level plug that could potentially lead to a total failure of the automatic transmission. Technical Service Bulletin (TSB) 26-01-060H instructions to inspect the oil level plug and transmission oil level and, if necessary, replace the automatic transmission.
26-01-057H DCS
Warranty Program/Extension
Certain 2026MY Sonata (DN8) and 2026MY Sonata Hybrid (DN8 HEV) vehicles may exhibit a fuel filler door that is difficult to open due to the push-type opener mechanism. Technical Bulletin (TSB) 26-01-057H provides instructions to inspect the fuel filler door push opener and, if necessary, replace the component to restore proper operation.
26-01-057H TSB
Warranty Program/Extension
Certain Sonata (DN8) and Sonata Hybrid (DN8 HEV) vehicles may exhibit a fuel filler door that is difficult to open due to the push-type opener mechanism. This bulletin provides instructions to inspect the fuel filler door push opener and, if necessary, replace the component to restore proper operation.
LA29-LA30 DCS
Warranty Program/Extension
Certain 2024-2026MY Sonata (DN8) and 2024-2026MY Sonata Hybrid (DN8 HEV) vehicles may exhibit intermittent battery discharge condition due to the air conditioning controller not fully powering down after the vehicle is turned off and parked. Technical Service Bulletins (TSB) 26-01-051H & 26-01-052H provide the procedure to update the ATCU (Air Temperature Control Unit) software; the revised logic improves controller shutdown to prevent battery drain and corrects a condition where the HVAC control display may appear blank when climate remote start is activated via Bluelink. Over-the-Air (OTA): This update can also be conducted via OTA. Customers can complete on their own if they have an active subscription to Hyundai Bluelink. A visit to the dealership is not required. Deployment of the OTA to Bluelink customers is planned to start the week of 07/13/26.
7/13/2026 TSB
Warranty Program/Extension
Certain Sonata (DN8) vehicles may exhibit intermittent battery discharge condition due to the air conditioning controller not fully powering down after the vehicle is turned off and parked. This bulletin provides the procedure to update the ATCU (Air Temperature Control Unit) software; the revised logic improves controller shutdown to prevent battery drain and corrects a condition where the HVAC control display may appear blank when climate remote start is activated via Bluelink.
26-AT-005H TSB
Service Bulletin/Repair Instructions
This bulletin provides information related to a Transmission Control Unit (TCU) software update for some vehicles equipped with an 8-speed wet dual clutch transmission (8WDCT). The software update revises the touch point learning variation, improving drivability and judder symptoms. Some 8WDCTs (indicated by a new part number) received an updated clutch spring. The correct TCU software update must be matched with the correct corresponding 8WDCT hardware, otherwise, drivability concerns may occur. This service procedure should be performed prior to any 8WDCT replacements done for drivability/judder concerns.
DTN DCS
Other
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.
DTN DL
Other
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.
26-01-035H TSB
Service Campaign
Some vehicles may exhibit a loss of connectivity or interruptions in the middle of using Bluelink functions. This may be due to an occasional disconnection on Verizon’s communication network. Follow the procedures in this bulletin to verify Bluelink Data Communication Unit (DCU) network connection and if needed, reset the DCU in Dealer Mode to resolve the connection.
26-AD-001H TSB
Service Bulletin/Repair Instructions
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).
TEB/TEBA DCS
Service Campaign
Hyundai Motor America is currently investigating an ongoing issue with software GDS event #1302. The matter is being investigated. We will provide an update once the issue is resolved and the suspension is lifted.
25-BD-012H TSB
Service Bulletin/Repair Instructions
This bulletin provides information regarding condensation related to the accumulated moisture in the headlamp, rear combination lamp, daytime running lamp (DRL), or fog lamp. This TSB illustrates the various causes of condensation inside the lamp assembly. Lamp assembly replacement is NOT necessary in most cases. This condition can be eliminated by turning on the lamps with the engine running for several minutes or during normal driving operation.
25-01-075H TSB
Service Campaign
Certain Sonata (DN8) vehicles may experience battery drain due to the air conditioning controller not shutting down completely while the vehicle is parked and turned off. This bulletin provides instructions to perform a software update for the ATCU (Air Temperature Control Unit).
25-01-075H/076H DCS
Service Campaign
Certain Sonata (DN8) and Sonata Hybrid (DN8 HEV) vehicles may experience battery drain due to the air conditioning controller not shutting down completely while the vehicle is parked and turned off. TSBs 25-01-075H (for Sonata vehicles) & 25-01-076H (Sonata Hybrid vehicles) provides instructions to perform a software update for the ATCU (Air Temperature Control Unit).