Acura bulletin B21100A
Acura filed this with NHTSA as a service bulletin dated Nov 11, 2021, received Oct 28, 2021, about the air bags — 2 documents under this number. It names 10 model years (2020–2021). 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 communicationServiceNews Article - There are several possible causes for the SRS DTC U3000-49 (Internal Failure of the SRS Unit) to be stored. If you can duplicate the DTC, the troubleshooting will take you through the step-by-step process in isolating the faulty component. In most situations, the SRS Unit should be last on the list of components to replace. Here is a quick tip for troubleshooting a faulty seat weight sensor.
Documents filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| B21100A | Service bulletin | Nov 11, 2021 | 10203504 | not yet checked |
| B21100A | Service bulletin | Oct 22, 2021 | 10202602 | 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 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 Acura B21100A 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 B21100A 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 B21100A cover?
The manufacturer filed it against 10 model years: 2021 Acura ILX, 2020 Acura ILX, 2020 Acura MDX, 2021 Acura NSX, 2020 Acura NSX, 2021 Acura RDX and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.