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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
20-01-031H-12020-08-07. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT. This bulletin describes the procedure to program the NFC Card only when no other NFC card has been paired to the vehicle previously.
Campaign T5A Dea2020-07-08. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM:SOFTWARE. This service campaign information is related to an Electronic Control Module (ECM) software update to revise the logic for DTC P030X: Cylinder “X” Misfire Detected and P0456: EVAP System Leakage Detected – Very Small Leak. This Service Campaign T5A will replace Service Campaign T4N.
20-01-027H2020-07-08. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT; ENGINE AND ENGINE COOLING. This bulletin provides information related to an Electronic Control Module (ECM) software update to revise the logic for DTC P030X: Cylinder “X” Misfire Detected and P0456: EVAP System Leakage Detected – Very Small Leak.
20-GI-003H2020-07-08. Service bulletin. ELECTRICAL SYSTEM. This bulletin provides information on the Launch Quality Monitoring Process (LQMP) for the 2020MY Hyundai Sonata Hybrid. After a new vehicle launch, Hyundai uses the LQMP to monitor all customer and dealer activities at a minimum of 100 days. The Sonata Hybrid LQMP helps improve model vehicle quality, and allows Hyundai to proactively respond to the Voice of the Customer (VOC).
20-EE-003H2020-05-07. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This bulletin provides information on identifying dealer stock vehicles with either: • A Battery SOC alert - low Battery State of Charge (SOC) at or below 50%. • A 30 Day alert - vehicle has not started and reported an SOC in 30 days.
20-EE-005H2020-04-07. Service bulletin. ELECTRICAL SYSTEM. Hyundai vehicles are equipped with Dark Current Control logic to help reduce amperage draw amount and conserve Battery State of Charge (SOC%). A selected Dark Current Control Mode will function when the vehicle is in the key off state, and will not affect vehicle functionality or performance.
20-EE-002H(1)2020-04-07. Service bulletin. ELECTRICAL SYSTEM. This bulletin describes the mandatory procedure to submit battery test data electronically for battery warranty claims by running the GDS Battery Claim App. The App must be run right after an incident battery is removed from the vehicle or after a battery charge is completed which qualifies for a warranty. It must be run at any time between RO open and close dates.
Campaign T4N Dea2020-03-06. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This service campaign provides information related to an ECM software update to revise the logic for DTC P0456: EVAP System Leakage Detected Very Small Leak.
20-01-005H(1)2020-03-06. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This bulletin provides information related to an Electronic Control Module (ECM) software update to revise the logic for DTC P0456: EVAP System Leakage Detected Very Small Leak.
Campaign T4L Dea2020-02-03. Service bulletin. ELECTRICAL SYSTEM. On certain Sonata (DN8) vehicles equipped with smart user features, the registered Hyundai app and the digital key card may not open the doors or start the vehicle when using these features.
20-BE-001H2020-02-03. Service bulletin. ELECTRICAL SYSTEM. This bulletin provides guidelines to inspect the USB, head unit, and multi-box for common connection conditions. 2. This bulletin presents guidelines to inspect for common Android Auto and Apple CarPlay connection conditions. 3. This bulletin provides physical differences between the USB 2.0 port and USB 3.0 port.

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