Acura over-the-air update D.1.6.4
What it saysOver The Air Update - Vehicles equipped with the System Updates application are capable of downloading and installing Over the Air System Updates. NHTSA’s full summary ↓
Acura filed this with NHTSA as an over-the-air update dated May 18, 2026, received Jun 2, 2026, about the electrical system — 2 documents under this number: B21673, B21674. It names 6 model years (2019–2023). An over-the-air update is not a safety recall — there is no NHTSA campaign number and no federal requirement — but it is usually work the manufacturer pays for on the vehicles it names; the dealer checks the VIN against the manufacturer’s list.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationOver The Air Update - Vehicles equipped with the System Updates application are capable of downloading and installing Over the Air System Updates. System Updates contain upgrades that fix a variety of operational errors and/or enhancements that add new functionality. Information for the various software releases can be found in this document. Software version: D.1.6.4
Documents filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| B21673 | Over-the-air update | May 18, 2026 | 11033180 | PDF, 619 KB |
| B21674 | Over-the-air update | May 18, 2026 | 11033179 | PDF, 568 KB |
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 1,069 complaints with NHTSA since 2015. 84 of them name Electrical System — 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 2019 Acura RDX, the 13 owners who gave an odometer reading for Electrical System reported it at a median of 6,250 miles. That figure is one model year’s, not the whole range this bulletin covers — medians from different model years are not averaged.
My TLX Tech 2023 lost complete power while I pulled up to a busy intersection on a dark and rainy day. As a puled to stop and my idle stop enabled the car was fine. Once I tried to accelerate the car immediately went into Park from Drive. All of the controls started to blink and the car powered down like a computer system who was on 0%.
2023 Acura TLX · Electrical System · filed with NHTSA Nov 10, 2023 · ODI 11554520
Car’s advertised anti-theft features are faulty. They have two tracking features with also both failed. When I contacted Acura they said this was a known issue and highly prevalent in NY, DC, FL, MD. Cars computer is cloneable and it takes less than 3 minutes to enter and steal without keys or breaking windows or enabling alarms
2023 Acura TLX · Electrical System · filed with NHTSA Nov 14, 2025 · ODI 11699323
We have a 2022 Acura TLX Type S and it has started to show an errors - Adaptive Damper System Problem. From what I can gather from reviewing articles on the Internet is that this problem is caused because of poor wiring design by Honda / Acura, which is causing speed sensors electronics to erode.
2022 Acura TLX · Electrical System · filed with NHTSA Jul 8, 2026 · ODI 11749059
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 electrical system
Source: same model, same component group21 other manufacturer communications filed against these Acura models under the same component group (electrical system), newest first. The eight newest are listed; the rest are on the Acura list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| F.1.4.1 | Over-the-air update | Jan 21, 2026 | Over the Air System Update - System updates contain upgrades that fix operational errors and/or provide a variety of enhancements, which add… |
| B24-046 | Service bulletin | Dec 18, 2024 | Service Bulletin - A coaxial cable terminal was not manufactured to proper specifications. An improperly manufactured terminal may lead to p… |
| B24-045 | Service bulletin | Dec 18, 2024 | Service Bulletin - A coaxial cable terminal was not manufactured to proper specifications. An improperly manufactured terminal may lead to p… |
| B23-025 | Service bulletin | Dec 18, 2024 | Service Bulletin - A coaxial cable terminal was not manufactured to proper specifications. An improperly manufactured terminal may lead to p… |
| B24-058 | Service bulletin | Dec 17, 2024 | Service Bulletin - Under certain circumstances when reversing near a chain-link fence or highly reflective surfaces, a parking and back-up s… |
| ONL6M309172024 | Other | Sep 18, 2024 | Owner Notification Letter - A coaxial cable terminal was not manufactured to proper specifications. An improperly manufactured terminal may… |
| BBOM07302024902 | Other | Jul 30, 2024 | Dealer Message - A coaxial cable terminal was not manufactured to proper specifications. An improperly manufactured terminal may lead to poo… |
| BTI&10182023901 | Service bulletin | Oct 18, 2023 | Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2022-2023 RDXs with a client complaint of the center infotain… |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Acura, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Acura D.1.6.4 a recall?
No. A over-the-air update 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 D.1.6.4 repair free?
A over-the-air update is usually paid by the manufacturer on the vehicles it names, within the terms and time limit the document sets; the dealer checks the VIN against the manufacturer’s list.
Which vehicles does D.1.6.4 cover?
The manufacturer filed it against 6 model years: 2021 Acura RDX, 2020 Acura RDX, 2019 Acura RDX, 2023 Acura TLX, 2022 Acura TLX, 2021 Acura TLX. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.