Hyundai bulletin 26-AT-002H
What it saysSome 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… NHTSA’s full summary ↓
Hyundai filed this with NHTSA as a service bulletin dated Feb 21, 2026, received Feb 24, 2026, about the power train. It names 6 model years (2021–2024). A service bulletin is not a safety recall: it is the manufacturer telling its dealers how to diagnose or repair a condition, and whether the work is paid for depends on the warranty in force. Quoting the number at a service desk can save a diagnosis.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationWhat it applies to, as the document itself states it — the build window in the manufacturer’s own words, read by machine from the PDF NHTSA serves. The build date is on the certification label in the driver’s door jamb; the dealer settles a borderline vehicle by its VIN.
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.
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| 26-AT-002H | Service bulletin | Feb 21, 2026 | 11028968 | PDF, 559 KB |
What the document itself lists
The manufacturer titles it “ELECTRIC OIL PUMP REPLACEMENT - DTC U028700”.
Parts the bulletin names
| Part number | Description | Qty | Find it |
|---|---|---|---|
| 46110-2F600QQH | Pump Assy-Electric Oil | — | eBay Motors → |
| 00232-19107 | ATF SP4-M | — | eBay Motors → |
| 45263-3B000 | O-Ring | 1 | eBay Motors → |
| 45262-3B100 | O-Ring | 1 | eBay Motors → |
| 45284-4G800 | Eye Bolt Assy | — | eBay Motors → |
Read by machine from the document NHTSA serves (7 pages), read Sep 29, 2026. A part number is shown only where it matches Hyundai’s own catalogue shape, an operation only with its code and time, and a description only where the reader got it whole; anything it could not settle is left out, and the PDF is the record. Times are the manufacturer’s warranty allowances, not a quote. Listings and prices on eBay Motors are the seller’s.
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The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themA vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
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What owners reported
Source: NHTSA complaint databaseOwners of the 6 model years this bulletin names have filed 1,593 complaints with NHTSA since 2015. 288 of them name Power Train — the same broad component group this bulletin is filed under. NHTSA groups complaints coarsely, so that means the same area of the vehicle, not necessarily the same fault.
On the 2021 Hyundai Santa Fe, the 12 owners who gave an odometer reading for Power Train reported it at a median of 21,000 miles. That figure is one model year’s, not the whole range this bulletin covers — medians from different model years are not averaged.
I am very distracted with this NEW car. This is the second time this has happened to my brand new Hyundai Tucson PHEV 2022. I was reversing on a slope, I changed gears to Drive, and then suddenly my car got stuck and stayed on neutral for no reason. Can’t turn off the car, or even change gears anymore. This is terrible!
2022 Hyundai Tucson · Power Train · filed with NHTSA Jul 5, 2023 · ODI 11530552
The vehicle was already running and in Drive. When I pressed the accelerator pedal to accelerate further, the vehicle would not accelerate. The RPMs did not increase and vehicle did not respond. No warning lights appeared. I had to press hazard lights coast to shoulder and turn vehicle off and on to regain power].
2023 Hyundai Tucson · Power Train · filed with NHTSA Oct 20, 2026 · ODI 11772556
I have been taking my 21 Santa Fe hybrid limited into the dealership for a year and a half for the same code . Powertrain code P040B00, and to this day they can not repair this issue. I looked it up and a ton of us are having issues with this same code. It should be investigated, and customers should be warned.
2021 Hyundai Santa Fe · Power Train · filed with NHTSA Jul 22, 2023 · ODI 11533831
In depth: 2023 Hyundai Santa Fe transmission and drivetrain problems → · 2022 Hyundai Santa Fe transmission and drivetrain problems → · 2021 Hyundai Santa Fe transmission and drivetrain problems → · 2022 Hyundai Tucson transmission and drivetrain problems →
A complaint is one owner’s account, not a defect finding, and a bulletin is not a recall. Nothing here says this bulletin was issued because of these complaints, or that the repair it describes fixed them. Complaint files on this site begin in 2015.
More bulletins about the power train
Source: same model, same component group25 other manufacturer communications filed against these Hyundai models under the same component group (power train), newest first. The eight newest are listed; the rest are on the Hyundai list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| 999A | Warranty extension | Aug 27, 2026 | Certain Santa Fe Hybrid (MX5A HEV) vehicles may experience a condition where a DTC triggered in the Hybrid Power Control Unit (HPCU) cannot… |
| 26-AT-005H | Service bulletin | Jun 5, 2026 | This bulletin provides information related to a Transmission Control Unit (TCU) software update for some vehicles equipped with an 8-speed w… |
| 26-AT-003H | Service bulletin | May 19, 2026 | Some Santa Fe (MX5A) and Santa Cruz (NXT) vehicles may exhibit a low idle or excessive vibration while in Drive or Reverse, or DTC P050600… |
| 26-AT-001H | Service bulletin | Mar 3, 2026 | Some Santa Cruz (NXT), Santa Fe (TMA, MX5A), and Sonata (DN8A) models may require replacement of the 8-speed wet dual clutch transmission… |
| TEJ | Service campaign | Oct 24, 2025 | Hyundai Motor America is currently investigating an ongoing concern with software GDS event #1306 for certain Hyundai Santa Fe (MX5A) vehicl… |
| TEJ / TEJA | Service campaign | Oct 8, 2025 | Certain Santa Fe (MX5A) and Santa Cruz (NXT) vehicles equipped with 8-speed dual clutch transmissions (8DCT) may set one of the high pressur… |
| 25-AT-001H | Service bulletin | May 30, 2025 | Certain Santa Fe (TMA) and Sonata (DN8/DN8A) vehicles equipped with 8-speed dual clutch transmissions (8DCT) may exhibit one of the DTCs lis… |
| 24-AT-001H-1 | Service bulletin | Dec 18, 2024 | This bulletin provides the procedure for updating the automatic transmission TCU (Transmission Control Unit) software to improve shift quali… |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Hyundai, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Hyundai 26-AT-002H a recall?
No. A service bulletin is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls, or on its page here.
Is the 26-AT-002H repair free?
Not automatically. A service bulletin describes how to diagnose or repair a condition; who pays depends on the warranty in force, any extension, and the dealer. Quoting the number can save a diagnosis either way. Every Hyundai warranty extension on file lists the ones Hyundai has filed.
Which vehicles does 26-AT-002H cover?
The manufacturer filed it against 6 model years: 2023 Hyundai Santa Fe, 2022 Hyundai Santa Fe, 2021 Hyundai Santa Fe, 2024 Hyundai Tucson, 2023 Hyundai Tucson, 2022 Hyundai Tucson. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone. The document itself sets the build window: 2021 - 2023 Santa Fe (TMA): built 19 Nov 2020 – 29 Dec 2023; 2022 - 2024 Tucson (NX4A): built 3 Feb 2021 – 19 Sep 2024 — the build date is on the certification label in the driver’s door jamb.