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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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Only bulletins with component: Electrical system are shown. Show all

Bulletins, newest first
25-BE-020H TSB2025-10-03. Service bulletin. ELECTRICAL SYSTEM. This bulletin provides information related to the changes introduced in the 2025 1st Navigation Map and Software Update. The changes may vary depending on vehicle type, model, and navigation system as described in this TSB.
25-01-010H-1 9B4 OL2025-08-22. Service campaign. ELECTRICAL SYSTEM. Certain Hyundai vehicles may exhibit a warning light with Diagnostic Trouble Code (“DTC”) P1BB20 due to a battery over voltage condition.
25-01-010H-1 DN2025-07-22. 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). The California Air Resources Board has determined that these vehicles may be releasing air pollutants which exceed Federal and California standards.
25-01-010H-1 TSB2025-07-22. Service campaign. 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 P1BB200 and enter Limp Mode.
25-BE-002H TSB2025-06-03. Service bulletin. ELECTRICAL SYSTEM. This bulletin provides information related to the changes introduced in the 2024 2nd Navigation Map and Software Update. The changes may vary depending on vehicle type, model, and navigation system. Refer to the 2024 2nd Navigation Map and Software Update Improvements section in this TSB for a list of specific changes. The software can be downloaded via Navigation Updater (NAU) and updated by USB. The NAU website is https://update.hyundai.com/US/EN/navigationUpdate. For certain models equipped with a relevant Bluelink package, the software may be downloaded and applied via OTA update.
25-01-024H-1 TSB2025-05-27. Service campaign. ELECTRICAL SYSTEM. Some vehicles may exhibit a loss of connectivity or interruptions in the middle of using Bluelink Service functions. This may be due to an irregular disconnection on Verizon’s communication network. Follow the procedure in this TSB to reestablish the connection via the AVN pinhole reset method.
25-EE-002H2025-05-02. Service bulletin. ENGINE; ELECTRICAL SYSTEM. Certain Sonata (DN8) and Sonata (DN8A) vehicles may experience issues with the air conditioning due to damaged wiring in the engine room junction box. This bulletin provides instructions to replace the multi-fuse, reroute the damaged wiring using the blower wiring kit, and replace the fuse label.
25-EE-002H TSB2025-04-30. Service bulletin. ELECTRICAL SYSTEM. Certain Sonata (DN8) and Sonata (DN8A) vehicles may experience issues with the air conditioning due to damaged wiring in the engine room junction box. This bulletin provides instructions to replace the multi-fuse, reroute the damaged wiring using the blower wiring kit, and replace the fuse label.
25-01-024H EM2025-04-18. Service campaign. ELECTRICAL SYSTEM. Some vehicles may exhibit a loss of connectivity or interruptions in the middle of using Bluelink Service functions. This may be due to an irregular disconnection on Verizon's communication network. If you are experiencing issues with remote commands, or other Bluelink services, please see the instructions below to reestablish the connection via the AVN pinhole reset method.
25-01-024H TSB2025-03-25. Service campaign. ELECTRICAL SYSTEM. Some vehicles may exhibit a loss of connectivity or interruptions in the middle of using Bluelink Service functions. This may be due to an irregular disconnection on Verizon’s communication network. Follow the procedure in this TSB to reestablish the connection via the AVN pinhole reset method.
9B1 OL2024-12-13. Service campaign. ELECTRICAL SYSTEM. The subject vehicles may have Diagnostic Trouble Code (DTC) P0451 stored in the ECU, which could cause the Check Engine Lamp to come on.
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-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.
23-01-093H2023-12-22. 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-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.
21-BE-004H2021-04-06. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. When using Wireless CarPlay, the system may intermittently auto disconnect. When Wireless CarPlay is disconnected, a pop up message “Phone Not Responding. Please reconnect it and try again” will appear on the radio screen.
21-01-009H2021-03-05. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM:SOFTWARE. This bulletin provides information related to an Electronic Control Module (ECM) software update which revises detection logic for DTC P2422: EVAP System Restricted Vent Valve logic.
21-01-007H2021-02-06. Service bulletin. ELECTRICAL SYSTEM. When using Wireless CarPlay, the system may intermittently auto disconnect. When Wireless CarPlay is disconnected, a pop up message “Phone Not Responding. Please reconnect it and try again” will appear on the radio screen. This bulletin describes the procedure to update the radio software to help reduce the disconnection occurrences.
20-BE-014H2021-01-09. Service bulletin. ELECTRICAL SYSTEM. When using Wireless CarPlay, the system may intermittently auto disconnect. When Wireless CarPlay is disconnected, a pop up message “Phone Not Responding. Please reconnect it and try again” will appear on the radio screen.
20-01-041H2020-11-06. Service bulletin. ELECTRICAL SYSTEM. Certain 2020 MY Ioniq Plug-In (AE PHEV), Ioniq Hybrid (AE HEV), and 2020 - 2021 MY Sonata Hybrid (DN8 HEV) may exhibit a check engine light ON with a DTC P17A0 (Navigation Control Module). This bulletin describes the procedure to install an Audio Video Navigation (AVN) software update to address the condition stated above.
20-01-039H2020-11-06. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This bulletin provides information and procedures for collecting OBD “In Use Monitor Performance Ratio” (IUMPR) data on certain 2019-2021MY vehicles at California dealers. This reporting is mandated by CARB (California Air Resources Board).
20-ST-003H2020-09-03. Service bulletin. STEERING:COLUMN; ELECTRICAL SYSTEM; STEERING:ELECTRIC POWER ASSIST SYSTEM. Certain vehicles may develop a bearing noise within the Motor Driven Power Steering (MDPS) column worm shaft assembly. If bearing noise is heard, follow the procedure in this bulletin to replace the worm shaft assembly.
20-ST-001H-12020-09-03. Service bulletin. STEERING:COLUMN; ELECTRICAL SYSTEM; STEERING:AUTOMATED/ADAPTIVE STEERING:MOTOR/ACTUATOR. This bulletin provides information regarding replacement of the column-mounted Motor Driven Power Steering (MDPS) system as separate components.

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