Mercedes-Benz bulletin ANN - CLA/174
What it saysIn some cases, we are seeing issues with the CLA/174. NHTSA’s full summary ↓
Mercedes-Benz filed this with NHTSA as a manufacturer communication dated May 23, 2026, received Jun 4, 2026, about the electrical system. It names 2 model years (2026–2027). A manufacturer communication 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 communicationIn some cases, we are seeing issues with the CLA/174. After updating the CPR to 1.3.7, a coding mismatch is occurring between the CIVIC174 & IDC control units causing a driver assistance msg in the cluster. We are currently working diligently toward a solution. If you need support, please create an XSS Diagnosis case with necessary ID1 support package and we are happy to support. Thank you for your patience.
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| ANN - CLA/174 | Other | May 23, 2026 | 11033421 | not found |
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 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 2 model years this bulletin names have filed 1 complaint 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.
More bulletins about the electrical system
Source: same model, same component group70 other manufacturer communications filed against the Mercedes-Benz CLA-Class under the same component group (electrical system), newest first. The eight newest are listed; the rest are on the Mercedes-Benz list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| LI46.00-P-081006 | Service bulletin | Sep 29, 2026 | Complaint The vehicle pulls to the left or right. Cause In vehicles with Car Package Release "CPR" 2.1.0 or prior, the calibration value for… |
| LI54.71-P-080956 | Service bulletin | Sep 25, 2026 | Complaint 174 with MB. OS 2.1.1 ‑ Driver Assistance System Limited in Instrument Cluster and Does Not Self‑Extinguish. When vehicle is shut… |
| LI82.60-P-080383 | Service bulletin | Sep 15, 2026 | Complaint Radio station cover art does not refresh when switching stations. The UI continues to show the old station’s artwork instead of up… |
| LI54.21-P-080326 | Service bulletin | Sep 9, 2026 | Complaint CEL light on with no drivability concerns. Cause Signal timing error. Remedy 167, 465: SW has been released. Update the FSAM to th… |
| LI54.30-P-080709 | Service bulletin | Sep 5, 2026 | Complaint Display message in the instrument cluster for "Active Brake Assist Inoperative" or "DISTRONIC inoperative". AND Fault code C1100FC… |
| LI27.19-P-080869 | Service bulletin | Aug 29, 2026 | Complaint Temporary no start condition with check engine light and multiple warning messages. When performing a quick test, the following fa… |
| LI82.90-P-080891 | Service bulletin | Aug 13, 2026 | Complaint • Driving assistance system fault messages are displayed in the driver display. • The switch lighting flashes at night/in the dark… |
| LI54.65-P-080132 | Service bulletin | Aug 12, 2026 | Complaint 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active Parking and Parking Assist… |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Mercedes-Benz, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Mercedes-Benz ANN - CLA/174 a recall?
No. A manufacturer communication 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 ANN - CLA/174 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 Mercedes-Benz warranty extension on file lists the ones Mercedes-Benz has filed.
Which vehicles does ANN - CLA/174 cover?
The manufacturer filed it against 2 model years: 2027 Mercedes-Benz CLA-Class, 2026 Mercedes-Benz CLA-Class. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.