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Service bulletin 23-AT-003H-1

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10241885
Published by NHTSA2023-09-06
Manufacturer's number23-AT-003H-1
Manufacturer's date2023-08-25
NHTSA componentPOWER TRAIN

NHTSA's summary

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.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Transmission and driveline

Vehicles listed
HYUNDAI PALISADE2020, 2021, 2022, 2023, 2024
HYUNDAI SANTA CRUZ2022, 2023
HYUNDAI SANTA FE2019, 2020, 2021, 2022, 2023
HYUNDAI SONATA2018, 2019, 2020, 2021, 2022
HYUNDAI TUCSON2022, 2023, 2024

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Recalls for the same vehicles and component
20234142023-07-27. Powertrain
23V5260002023-07-27. POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT:PUMP
20225682022-10-06. Powertrain
22V7460002022-10-06. POWER TRAIN:AUTOMATIC TRANSMISSION
20181352018-03-16. Powertrain

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
26-AT-005H TSB2026-06-16. Service bulletin. 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.
26-01-028H2026-03-30. Warranty extension. Certain Santa Cruz (NXT) vehicles equipped with 8-speed dual clutch transmissions (8DCT) may set one of the high pressure electric oil pump (HP EOP) DTCs listed below. This bulletin provides the service procedure to update the Transmission Control Unit (TCU) with improved logic to address these DTCs and enhance operation of the 8DCT.
26-AT-001H TSB2026-03-11. Service bulletin. Some Santa Cruz (NXT), Santa Fe (TMA, MX5A), and Sonata (DN8A) models may require replacement of the 8-speed wet dual clutch transmission (8WDCT) when the vehicle sets one of the high pressure electric oil pump (HP EOP) DTCs listed below. This bulletin provides instructions to replace the 8WDCT.
26-AT-002H2026-02-24. Service bulletin. Some Santa Fe (TMA) and Tucson (NX4A) vehicles equipped with a 2.5L GDI engine and 8 speed automatic transmission may have DTC U028700 (Lost Communication With Trans Fluid Pump Module) set by the transmission Electric Oil Pump (EOP). This DTC can cause the Idle Stop & Go (ISG) system to become inoperative. Follow the procedure in this bulletin to replace the Electric Oil Pump on affected vehicles.
25-AT-001H TSB2025-06-03. Service bulletin. Certain Santa Fe (TMA) and Sonata (DN8/DN8A) vehicles equipped with 8-speed dual clutch transmissions (8DCT) may exhibit one of the DTCs listed below, related to the high pressure electric oil pump (HP EOP). Follow the procedures in this TSB to update the Transmission Control Unit (TCU) to the latest sensorless logic on affected vehicles, and then perform air bleeding and transmission learning.
24-AT-001H-12024-12-21. Service bulletin. This bulletin provides the procedure for updating the automatic transmission TCU (Transmission Control Unit) software to improve shift quality, judder and hesitation when accelerating.
24-AT-002H2024-04-16. Service bulletin. 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. 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-AT-001H2024-03-05. Service bulletin. This bulletin provides the procedure for updating the automatic transmission TCU and ECU software (Santa Fe ONLY) to improve shift quality, judder with ISG enabled and hesitation when accelerating.
23-FL-007H2023-12-22. Service bulletin. This bulletin provides the procedure to update the Transmission Control Module (TCM) for the 2022MY Tucson (NX4/NX4a) vehicles and the Engine Control Module (ECM) for the 2022-24MY Tucson vehicles to improve operation of the Idle Stop and Go (ISG) system. Under certain circumstances the vehicle may not restart after ISG system has engaged and require a manual restart due to the lack of intake manifold pressure recovery.