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Service bulletins for the 2020 Hyundai Sonata

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

124 on file from NHTSA, as of 2026-10-19.

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Bulletins, newest first
24-EM-001H2024-08-07. Service bulletin. ENGINE. Certain 20-22MY Sonata (DN8a), 21-23MY Santa Fe (TMa), and 22-23MY Tucson (NX4a) vehicles may experience a warning lamp illumination for a diagnostic trouble code P2181 that is related to the Integrated Thermal Management Module (ITM). Follow the service procedure outlined in this bulletin to replace the ITM.
24-BE-001H-12024-08-07. Service bulletin. ELECTRICAL SYSTEM. Some vehicles equipped with the AVN 5th Gen Wide system may exhibit a condition where the radio app crashes frequently when entering radio mode and/or displays a message that reads “Uneven Road Ahead, Drive carefully” on the cluster along with a warning sound. Follow the procedure outlined in this bulletin to update the AVN software to resolve this condition.
24-01-054H2024-08-07. Service campaign. ELECTRICAL SYSTEM. Certain Elantra hybrid (CN7 HEV), Sonata hybrid (DN8 HEV), and Tucson hybrid (NX4 HEV) vehicles may exhibit a warning light due to DTC Code P1BB20 (12V Lithium Battery Cell Voltage High). Follow the procedure in TSB 24-01-054H (or latest version) to perform the update the Battery management System (BMS) software.
SERVICE CAMPAIGN 9B42024-08-07. Service bulletin. ELECTRICAL SYSTEM. This bulletin provides the procedure to update the software for the Battery Management System (BMS) on certain Elantra Hybrid (CN7 HEV), Sonata Hybrid (DN8 HEV), and Tucson Hybrid (NX4 HEV) vehicles that may exhibit a warning light with DTC P1BB20.
24-AT-002H2024-04-16. Service bulletin. POWER TRAIN. This TSB provides a procedure to diagnose and replace, if necessary, an automatic transmission with Incorrect Ratio DTC (transmission clutch slip in gear above limit) listed on Page 2.
24-FL-002H2024-03-05. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM); ENGINE AND ENGINE COOLING. This bulletin provides the procedure to update the Engine Control Module (ECM) and/or the Transmission Control Module (TCM) for 2020-2023MY Sonata (DN8/DN8a) vehicles to improve operation of the Idle Stop and Go (ISG) system. Under certain circumstances the vehicle may not restart after the ISG system has engaged and requires a manual restart due to the lack of intake manifold pressure recovery.
24-BD-001H2024-03-05. Service bulletin. VISIBILITY; VISIBILITY/WIPER. This bulletin contains information about the proper removal of the windshield wiper blade protective cover on all models. If the protective cover is not removed correctly, there is a possibility of the rubber insert and rail spring becoming partially separated on the inner side of the wiper blade, which could lead to poor wiping performance and/or possible scratching of the windshield glass. Follow the procedure in this bulletin to properly remove the windshield wiper blade protective cover on all new wiper blades.
24-BE-001H2024-02-05. Service bulletin. ELECTRICAL SYSTEM. Some vehicles equipped with the AVN 5th Gen Wide system may exhibit a condition where the radio app crashes frequently when entering radio mode and/or displays a message that reads “Uneven Road Ahead, Drive carefully” on the cluster along with a warning sound. Follow the procedure outlined in this bulletin to update the AVN software to resolve this condition.
23-01-093H2024-02-05. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin provides the procedure to update the Hybrid Control Unit (HCU) and Dual Automatic Temperature Control (DATC) software to help improve coolant flow to the Exhaust Heat Recovery System (EHRS).
23-EM-009H2023-12-22. Service bulletin. ENGINE AND ENGINE COOLING; POWER TRAIN. Certain 2020-2023MY Sonata Hybrid (DN8 HEV) vehicles may exhibit coolant leakage, engine overheating, and white smoke from the exhaust due to an internal leak at the Exhaust Heat Recovery System (EHRS) portion of the center muffler assembly. Follow the procedure outlined in this bulletin to repair this condition after confirming EHRS is leaking internally.
23-01-093H2023-12-22. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. This bulletin provides the procedure to update the Hybrid Control Unit (HCU) and Dual Automatic Temperature Control (DATC) software to help improve coolant flow to the Exhaust Heat Recovery System (EHRS).
23-EM-005H2023-12-15. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin provides important checkpoint guidelines when performing engine oil and filter change services.
23-AT-006H-22023-11-30. Service bulletin. POWER TRAIN. This TSB provides information to diagnose the push button shifter operation.
23-AT-008H-12023-10-02. Service bulletin. POWER TRAIN. If you are servicing an 8-speed front-wheel-drive vehicle equipped with automatic transaxle with one or more of the DTC or symptoms listed below, refer to the Service Procedure to diagnose the condition. • DIAGNOSTIC TROUBLE CODES: ➢ P070500 - Transmission range sensor circuit malfunction ➢ P070512 - Transmission range sensor circuit malfunction ➢ P070514 - Transmission range sensor circuit malfunction ➢ P07051C - Transmission range sensor circuit malfunction ➢ P070600 - Transmission range sensor circuit range/performance ➢ P070661 - Transmission range sensor circuit range/performance ➢ P070696 - Transmission range sensor circuit range/performance • SYMPTOMS: ➢ Malfunction Indicator Light (MIL) illuminated ➢ 5th gear fail-safe ➢ Intermittently won’t shift into D or R ➢ Intermittently won’t shift out of Park ➢ Intermittent ly no engine cr ank/n o start in “P” or “N” with or without MIL or DTC.
23-AT-003H-12023-09-06. Service bulletin. POWER TRAIN. If you are servicing an 8-speed vehicle with a “Check Engine” light on and one or more of the DTC listed, follow the service procedure and replace the related solenoid and harness.
23-HC-002H2023-09-06. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM); POWER TRAIN. This bulletin provides information related to the Engine Control Module (ECM) software update and coolant replacement for 2020-2023MY Sonata Hybrid (DN8 HEV) vehicles to improve the coolant filling mode by discharging air bubbles.
23-EE-009H2023-09-06. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin provides warranty procedure for EGR Valve replacement related to DTC P0401 EGR Flow Insufficient on 2020 and 2021MY Sonata (DN8a) equipped with 2.5 GDI Vehicles.
23-AT-006H-12023-09-05. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION; POWER TRAIN. This TSB provides information to diagnose the push button shifter operation. If you are servicing a vehicle with any symptoms listed below or DTCs (listed on Page 2) , follow the Service Procedure on Page 3. SYMPTOMS: • “Shifter System Malfunction” displayed in the cluster • Won’t shift into or out of gear or won’t shift out of Park • Incorrect gear display in cluster and/or won’t start
23-BE-007H2023-08-02. Service bulletin. EQUIPMENT:ELECTRICAL:INFOTAINMENT:SOFTWARE; ELECTRICAL SYSTEM. This Service Information bulletin provides information on how to update the Apple Carplay software from Hyundai’s Navigation Updates page. The current version of Google Maps has 10 times the data transmission compared to the previous version. As a countermeasure, an update with a frame skip logic has been added to resolve the data congestion with Google Maps.
23-AT-008H2023-08-02. Service bulletin. POWER TRAIN. If you are servicing an 8-speed front-wheel-drive vehicle equipped with automatic transaxle with one or more of the DTC or symptoms listed below, refer to the Service Procedure to diagnose the condition.
23-BD-007H2023-05-04. Service bulletin. STRUCTURE:BODY. Hyundai applies a Paint Protection Film (PPF) on new vehicles before delivery to dealerships. It provides a barrier between the paint and contaminants, such as rail dust, acid rain, and industrial fallout. In rare cases, the paint can become clouded under the PPF. These spots are the result of moisture trapped between the PPF and the paint.
23-EE-005H2023-05-02. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin provides the procedure to repair poor pin tension at joint connector JE102 in certain Sonata (1.6 T-GDI engine) with one or more DTC.
23-EE-006H2023-05-02. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin provides the procedure to repair poor pin tension at joint connector JE202 in certain Sonata (2.5L GDI engine) with one or more DTC.
23-AT-003H2023-05-02. Service bulletin. ENGINE AND ENGINE COOLING. If you are servicing an 8-speed vehicle with a “Check Engine” light on and one or more of the DTC listed, follow the service procedure and replace the related solenoid and harness.
23-BD-002H2023-02-02. Service bulletin. VISIBILITY. 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.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.