BMW bulletin B521923
BMW filed this with NHTSA as a service bulletin dated May 4, 2026, received Jan 3, 2024, about the seats — 5 documents under this number. It names 5 model years (2022–2026). 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.
What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationIn vehicles equipped with the second row 60% / 40% split seat, the flex cable assembly can come out of the seat rail mechanism (circled). This stops the forwards and backwards travel of the seat.
Documents filed under this number
| Document | Kind | Dated | NHTSA id |
|---|---|---|---|
| B521923 | Service bulletin | May 4, 2026 | 11032738 |
| B521923 | Service bulletin | Jan 15, 2026 | 11027769 |
| B521923 | Service bulletin | Mar 27, 2025 | 11016438 |
| B521923 | Service bulletin | Dec 17, 2024 | 11012090 |
| B521923 | Service bulletin | Dec 20, 2023 | 10247565 |
The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5; the full text comes from the manufacturer or a dealer. 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. Quote it 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.
Common questions
Source: NHTSA, 49 CFR 579.5Is BMW B521923 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 B521923 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.
Which vehicles does B521923 cover?
The manufacturer filed it against 5 model years: 2026 BMW X7, 2025 BMW X7, 2024 BMW X7, 2023 BMW X7, 2022 BMW X7. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.