BMW bulletin B170121
BMW filed this with NHTSA as a service bulletin dated Apr 1, 2022, received May 31, 2022, about the engine and engine cooling — 2 documents under this number. It names 65 model years (2016–2021). 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 communicationThe quick disconnect coupling on the cylinder head coolant vent line could break at the cylinder head. This would lead to loss of coolant from the engine.
Documents filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| B170121 | Service bulletin | Apr 1, 2022 | 10212788 | not yet checked |
| B170121 | Service bulletin | Feb 1, 2022 | 10214256 | not yet checked |
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 themand 2 more model years on this site.
Also filed against model years this site has no page for: 2017 BMW 335I; 2020 BMW 340I; 2017 BMW 530E; 2017 BMW 740LE; 2018 BMW 740LE; 2017 BMW 740LI; 2018 BMW 740LI; 2017 BMW 750LI; 2018 BMW 750LI; 2017 BMW 750LXI; 2017 BMW 750XI; 2018 BMW 8 Series; 2018 BMW B7 Alpina; 2017 BMW M235I; 2017 BMW M4; 2018 BMW M4; 2017 BMW M550I; 2017 BMW M6; 2018 BMW M6; 2017 BMW M760LI; 2018 BMW M760LI; 2018 BMW M850I; 2017 BMW X1 SAV.
A 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 B170121 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 B170121 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 B170121 cover?
The manufacturer filed it against 65 model years: 2021 BMW 2 Series, 2020 BMW 2 Series, 2019 BMW 2 Series, 2018 BMW 2 Series, 2017 BMW 2 Series, 2016 BMW 2 Series and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.