GM over-the-air update 661.40
What it saysFixes to help prevent loss of functionality for OnStar, infotainment apps, and connectivity features. NHTSA’s full summary ↓
GM filed this with NHTSA as an over-the-air update dated Jun 2, 2026, received Apr 30, 2026 — 6 documents under this number. It names 11 model years across Chevrolet and GMC (2024–2026). 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.
One page for every brand it was filed under. Each brand’s bulletins: Chevrolet · GMC.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communication• Fixes to help prevent loss of functionality for OnStar, infotainment apps, and connectivity features. • Improvements to the performance of vehicle software updates. • Fixes to help prevent loss of functionality for connectivity features, including maps and Wi-Fi. • Fixes to help prevent erroneous emergency calls from vehicle. • Fixes for deleting digital keys. • Fixes to help ensure proper functionality for mobile app features. • Improvements to the performance of Super Cruise.
Documents filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| 661.40 | Over-the-air update | Jun 2, 2026 | 11033768 | PDF, 189 KB |
| 661.40 | Over-the-air update | Jun 2, 2026 | 11033767 | PDF, 197 KB |
| 661.40 | Over-the-air update | May 26, 2026 | 11032933 | PDF, 190 KB |
| 661.40 | Over-the-air update | Apr 28, 2026 | 11031824 | PDF, 196 KB |
| 661.40 | Over-the-air update | Apr 28, 2026 | 11031823 | PDF, 197 KB |
| 661.40 | Over-the-air update | Apr 1, 2026 | 11031767 | PDF, 195 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 themChevrolet 6 model years
GMC 5 model years
Also filed against model years this site has no page for: 2026 GMC Hummer EV Pickup; 2026 GMC Hummer EV SUV.
A 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 9 model years this bulletin names have filed 1,503 complaints with NHTSA since 2015.
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.
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Chevrolet and GMC, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is GM 661.40 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 661.40 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 661.40 cover?
The manufacturer filed it against 11 model years across 2 brands (Chevrolet and GMC): 2026 Chevrolet Blazer, 2024 Chevrolet Blazer, 2026 Chevrolet Equinox, 2026 Chevrolet Silverado, 2025 Chevrolet Silverado, 2024 Chevrolet Silverado and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.