GM bulletin 25-NA-025
What it saysThis bulletin provides a procedure to check the wiring harness for a possible short that may cause the code to set and not just to replace the evaporative vacuum leak pump. NHTSA’s full summary ↓
GM filed this with NHTSA as a service bulletin dated Feb 18, 2025, received Feb 28, 2025, about the electrical system. It names 4 model years across Chevrolet and Buick (2025). 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 · Buick.
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 bulletin provides a procedure to check the wiring harness for a possible short that may cause the code to set and not just to replace the evaporative vacuum leak pump.
Trouble codes it names: P0690 P16B3 P2420 all 3 read from the document itself; NHTSA’s summary names none
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| 25-NA-025 | Service bulletin | Feb 18, 2025 | 11014597 | PDF, 128 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 2 model years
Buick 2 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 4 model years this bulletin names have filed 178 complaints with NHTSA since 2015. 100 of them name Electrical System, Engine — 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.
Second complete powertrain failure on March 14, 2026 at 13,993 miles, nine days after first repair (complete transmission replacement for bone-dry sealed transmission). Symptoms: sudden loss of power on highway (unable to exceed 20 mph with accelerator fully depressed), hollow sound, noise described as "like a rock tumbling around…
2025 Buick Encore · Engine · filed with NHTSA Apr 1, 2026 · ODI 11728488
My vehicle started overheating out of no where towed it to the shop, it’s been there for 2 weeks they’re actively waiting for a manufacturer engineer to tell them what to do because they can’t figure out how to fix it. On top of that there have been a lot of overheating issues cause by different parts on the vehicle.
2025 Chevrolet Trailblazer · Engine · filed with NHTSA Apr 16, 2026 · ODI 11731715
The contact owned a 2025 Buick Encore GX. The contact stated that while driving at an undisclosed speed, the GPS failed to operate properly. Additionally, the air conditioning system was inoperable. The contact stated that while driving in the heat, the contact to briefly became unconscious.
2025 Buick Encore · Electrical System · filed with NHTSA Jul 17, 2026 · ODI 11751200
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 group77 other manufacturer communications filed against these GM models under the same component group (electrical system), newest first. The eight newest are listed; the rest are on the Chevrolet list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| 18-NA-180 | Service bulletin | Sep 4, 2025 | This Warranty Administration service bulletin provides Lithium-Ion battery Exchange Process and Transaction Submission information. |
| 23-NA-119 | Service bulletin | Sep 3, 2025 | This service bulletin provides service procedure information to correct a customer concern of Shift to Park Displayed on DIC When Vehicle is… |
| 22-NA-242 | Service bulletin | Apr 24, 2025 | This warranty administration bulletin provides information for dealers/technicians on System Reset and Connector Reconnect Labor Code Number… |
| 23-NA-198 | Service bulletin | Apr 14, 2025 | This service bulletin provides repair information to correct a customer concern of the HVAC Not Cooling Cabin During a Remote Start. |
| 24-NA-229 | Service bulletin | Apr 10, 2025 | This bulletin provides a procedure on how to check for a battery drain utilizing the Picoscope and how to measure the load on the system tha… |
| 25-NA-087 | Service bulletin | Apr 3, 2025 | This service bulletin provides information on the proper Reflective High Temperature Heat and/or Insulating Tape to use for certain repairs… |
| 13-08-116-001K | Service bulletin | Mar 31, 2025 | The intent of this service bulletin is to identify aftermarket ALDL or DLC interface devices as potential sources for causing multiple custo… |
| 25-NA-071 | Service bulletin | Mar 21, 2025 | This service bulletin provides repair procedures for radio software update version 169.4 to correct customer concerns of radio software issu… |

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 Buick, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is GM 25-NA-025 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 25-NA-025 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 25-NA-025 cover?
The manufacturer filed it against 4 model years across 2 brands (Chevrolet and Buick): 2025 Buick Encore, 2025 Buick Envista, 2025 Chevrolet Trailblazer, 2025 Chevrolet Trax. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.