GM bulletin PIT5509M
What it saysThis PI provides diagnostic tips for diagnosing electric trailer brakes issues. NHTSA’s full summary ↓
GM filed this with NHTSA as a service bulletin dated May 14, 2026, received May 19, 2026. It names 119 model years across Chevrolet, GMC and Cadillac (2016–2026). 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 · Cadillac.
Get the next GM bulletin for your model by email Weekly, only when something new is filed. Nothing else; one-click unsubscribe.
What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationThis PI provides diagnostic tips for diagnosing electric trailer brakes issues.
Trouble codes it names: C1114 all 1 read from the document itself; NHTSA’s summary names none
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| PIT5509M | Service bulletin | May 14, 2026 | 11032777 | PDF, 806 KB |
What the document itself lists
Part the bulletin names
| Part number | Description | Qty | Find it |
|---|---|---|---|
| 23404450 | — | — |
Read by machine from the document NHTSA serves (9 pages), read Sep 29, 2026. A part number is shown only where it matches GM’s own catalogue shape, an operation only with its code and time, and a description only where the reader got it whole; anything it could not settle is left out, and the PDF is the record. Times are the manufacturer’s warranty allowances, not a quote. Listings and prices on eBay Motors are the seller’s.
Affiliate disclosure: some links on this page are affiliate links. If you request a quote or buy through them we may earn a commission at no extra cost to you. Nothing on this page changes because of it.
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 62 model years
and 22 more on this site: 2019 Chevrolet Silverado 3500HD, 2018 Chevrolet Silverado 3500HD, 2017 Chevrolet Silverado 3500HD, 2016 Chevrolet Silverado 3500HD, 2024 Chevrolet Suburban, 2023 Chevrolet Suburban, 2022 Chevrolet Suburban, 2021 Chevrolet Suburban, 2020 Chevrolet Suburban, 2019 Chevrolet Suburban, 2018 Chevrolet Suburban, 2017 Chevrolet Suburban, 2016 Chevrolet Suburban, 2024 Chevrolet Tahoe, 2023 Chevrolet Tahoe, 2022 Chevrolet Tahoe, 2021 Chevrolet Tahoe, 2020 Chevrolet Tahoe, 2019 Chevrolet Tahoe, 2018 Chevrolet Tahoe, 2017 Chevrolet Tahoe, 2016 Chevrolet Tahoe.
GMC 53 model years
and 45 more on this site: 2018 GMC Canyon, 2017 GMC Canyon, 2016 GMC Canyon, 2026 GMC Sierra, 2025 GMC Sierra, 2024 GMC Sierra, 2023 GMC Sierra, 2022 GMC Sierra, 2021 GMC Sierra, 2020 GMC Sierra, 2019 GMC Sierra, 2018 GMC Sierra, 2017 GMC Sierra, 2016 GMC Sierra, 2026 GMC Sierra 2500HD, 2025 GMC Sierra 2500HD, 2024 GMC Sierra 2500HD, 2023 GMC Sierra 2500HD, 2022 GMC Sierra 2500HD, 2021 GMC Sierra 2500HD, 2020 GMC Sierra 2500HD, 2019 GMC Sierra 2500HD, 2018 GMC Sierra 2500HD, 2017 GMC Sierra 2500HD, 2016 GMC Sierra 2500HD, 2026 GMC Sierra 3500HD, 2025 GMC Sierra 3500HD, 2024 GMC Sierra 3500HD, 2023 GMC Sierra 3500HD, 2022 GMC Sierra 3500HD, 2021 GMC Sierra 3500HD, 2020 GMC Sierra 3500HD, 2019 GMC Sierra 3500HD, 2018 GMC Sierra 3500HD, 2017 GMC Sierra 3500HD, 2016 GMC Sierra 3500HD, 2024 GMC Yukon, 2023 GMC Yukon, 2022 GMC Yukon, 2021 GMC Yukon, 2020 GMC Yukon, 2019 GMC Yukon, 2018 GMC Yukon, 2017 GMC Yukon, 2016 GMC Yukon.
Cadillac 4 model years
A vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
Email me new GM bulletins for one of these models
A weekly email, sent only in a week when GM files something new with NHTSA for the model you pick — service bulletins, campaigns, warranty extensions, over-the-air notices, every model year. Nothing else is sent; one-click unsubscribe in every message. Separate from recall alerts.
What owners reported
Source: NHTSA complaint databaseOwners of the 119 model years this bulletin names have filed 21,903 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 and Cadillac, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is GM PIT5509M 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 PIT5509M 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 PIT5509M cover?
The manufacturer filed it against 119 model years across 3 brands (Chevrolet, GMC and Cadillac): 2024 Cadillac Escalade, 2023 Cadillac Escalade, 2022 Cadillac Escalade, 2021 Cadillac Escalade, 2026 Chevrolet Colorado, 2025 Chevrolet Colorado and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.