GM bulletin PIT6507
What it saysThis PI communicates information on a SPS programming issue causing Serial Data Authentication Configuration to fail. NHTSA’s full summary ↓
GM filed this with NHTSA as a service bulletin dated Apr 20, 2026, received Apr 29, 2026. It names 8 model years across Chevrolet, GMC, Buick and Cadillac (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.
One page for every brand it was filed under. Each brand’s bulletins: Chevrolet · GMC · Buick · Cadillac.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationThis PI communicates information on a SPS programming issue causing Serial Data Authentication Configuration to fail.
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| PIT6507 | Service bulletin | Apr 20, 2026 | 11031717 | PDF, 105 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 3 model years
GMC 1 model year
Buick 1 model year
Cadillac 3 model years
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 8 model years this bulletin names have filed 1,473 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, GMC, Buick and Cadillac, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is GM PIT6507 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 PIT6507 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. Every GM warranty extension on file lists the ones GM has filed.
Which vehicles does PIT6507 cover?
The manufacturer filed it against 8 model years across 4 brands (Chevrolet, GMC, Buick and Cadillac): 2021 Buick Envision, 2021 Cadillac CT4, 2021 Cadillac CT5, 2021 Cadillac Escalade, 2021 Chevrolet Corvette, 2021 Chevrolet Suburban and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.