Cadillac bulletin 25-NA-026
What it saysThis service bulletin provides repair information to correct a customer concern of Service Drivers Assist Message Illuminated, Super Cruise Inoperable, and DTC U1624 Setting. NHTSA’s full summary ↓
Cadillac filed this with NHTSA as a service bulletin dated Feb 11, 2025, received Feb 27, 2025, about the electrical system. It names 1 model year (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.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationThis service bulletin provides repair information to correct a customer concern of Service Drivers Assist Message Illuminated, Super Cruise Inoperable, and DTC U1624 Setting.
Trouble codes it names: U1624
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| 25-NA-026 | Service bulletin | Feb 11, 2025 | 11014569 | PDF, 835 KB |
What the document itself lists
Labour operation and the time the manufacturer allows
| Operation | Description | Time |
|---|---|---|
| 2880027 | Update the TCM Utility File | 0.3 hrs |
Read by machine from the document NHTSA serves (6 pages), read Sep 30, 2026. A part number is shown only where it matches Cadillac’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.
Doing the repair yourself, or pricing it before the shop does? Search the part by fitment on eBay Motors — the listing and the price are the seller’s.
Find the adaptive cruise control for the 2025 CT4 →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.
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 1 model year this bulletin names have filed 2 complaints with NHTSA since 2015. 1 of them name Forward Collision Avoidance — 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.
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 group62 other manufacturer communications filed against the Cadillac CT4 under the same component group (electrical system), newest first. The eight newest are listed; the rest are on the Cadillac list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| 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… |
| 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… |
| 24-NA-098 | Service bulletin | Mar 21, 2025 | This service bulletin provides information for dealers/technicians on Service Programming System (SPS) Error Codes E4398, E4399, E4401, E440… |
| 15-06-03-001F | Service bulletin | Mar 12, 2025 | This service bulletin provides information to diagnose batteries that have set for a long period of time and/or cold weather climates and te… |
| 23-NA-064 | Service bulletin | Jan 29, 2025 | This service bulletin provides information on the Transport Mode Feature, also known as Logistics mode, which is used to increase the 12V Ba… |
| 21-NA-135 | Service bulletin | Jan 28, 2025 | This service bulletin provides information to inform dealership personnel about Law Enforcement and Government vehicles that request to disa… |

Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Cadillac, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Cadillac 25-NA-026 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-026 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.
Which vehicles does 25-NA-026 cover?
The manufacturer filed it against 1 model year: 2025 Cadillac CT4. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.