Mercedes-Benz bulletin LI82.85-P-079271
What it saysComplaint After a software update of HERMES communication module N112/9 has been performed on a gray import vehicle, the message "SOS - Service not activated" is displayed in the instrument cluster. NHTSA’s full summary ↓
Mercedes-Benz filed this with NHTSA as a service bulletin dated May 22, 2025, received May 29, 2025, about the electrical system. It names 84 model years (2016–2024). 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 communicationComplaint After a software update of HERMES communication module N112/9 has been performed on a gray import vehicle, the message "SOS - Service not activated" is displayed in the instrument cluster. Cause The message "SOS - Service not activated" tells the customer that "over-the-air" registration of the vehicle with the Mercedes Intelligent Cloud is not possible. On a gray import vehicle, this is due to the fact that the SIM card installed in the HERMES communications module cannot dial into the mobile phone network in the importing country. Remedy The only way of avoiding the message in the instrument cluster is to deactivate the HERMES module using the 09o deactivation process after obtaining the customer's consent. After deactivation, the HERMES control unit (N112/9) has the operating status "Inoperative". The message "SOS not ready" appears in the audio/COMAND display (A40/8) and may also appear in the instrument cluster. This display message tells the customer that the emergency call function is not available. In addition, the workshop must attach a label (2 x part number A9078172900 required) to the cover of the emergency call button in the overhead control panel and to the emergency call button itself. Replacing the hardware of the HERMES communication module is not effective.
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| LI82.85-P-079271 | Service bulletin | May 22, 2025 | 11018626 | PDF, 384 KB |
What the document itself lists
Part the bulletin names
| Part number | Description | Qty | Find it |
|---|---|---|---|
| A9078172900 | — | — |
Read by machine from the document NHTSA serves (3 pages), read Sep 30, 2026. A part number is shown only where it matches Mercedes-Benz’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.
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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 themand 42 more on this site: 2018 Mercedes-Benz G-Class, 2017 Mercedes-Benz G-Class, 2016 Mercedes-Benz G-Class, 2016 Mercedes-Benz GL-Class, 2020 Mercedes-Benz GLA-Class, 2019 Mercedes-Benz GLA-Class, 2018 Mercedes-Benz GLA-Class, 2017 Mercedes-Benz GLA-Class, 2016 Mercedes-Benz GLA-Class, 2023 Mercedes-Benz GLC-Class, 2022 Mercedes-Benz GLC-Class, 2021 Mercedes-Benz GLC-Class, 2020 Mercedes-Benz GLC-Class, 2019 Mercedes-Benz GLC-Class, 2018 Mercedes-Benz GLC-Class, 2017 Mercedes-Benz GLC-Class, 2016 Mercedes-Benz GLC-Class, 2019 Mercedes-Benz GLE-Class, 2018 Mercedes-Benz GLE-Class, 2017 Mercedes-Benz GLE-Class, 2016 Mercedes-Benz GLE-Class, 2019 Mercedes-Benz GLS-Class, 2018 Mercedes-Benz GLS-Class, 2017 Mercedes-Benz GLS-Class, 2016 Mercedes-Benz GLS-Class, 2021 Mercedes-Benz S-Class, 2020 Mercedes-Benz S-Class, 2019 Mercedes-Benz S-Class, 2018 Mercedes-Benz S-Class, 2017 Mercedes-Benz S-Class, 2016 Mercedes-Benz S-Class, 2020 Mercedes-Benz SL-Class, 2019 Mercedes-Benz SL-Class, 2018 Mercedes-Benz SL-Class, 2017 Mercedes-Benz SL-Class, 2016 Mercedes-Benz SL-Class, 2020 Mercedes-Benz SLC-Class, 2019 Mercedes-Benz SLC-Class, 2018 Mercedes-Benz SLC-Class, 2017 Mercedes-Benz SLC-Class, 2016 Mercedes-Benz SLC-Class, 2016 Mercedes-Benz SLK-Class.
Also filed against model years this site has no page for: 2017 Mercedes-Benz GL450; 2017 Mercedes-Benz GL550.
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 82 model years this bulletin names have filed 2,979 complaints with NHTSA since 2015. 467 of them name Electrical System — 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.
The contact owns a 2020 Mercedes-Benz CLS450. The contact received notification of NHTSA Campaign Number: 22V533000 (Electrical System) however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair.
2020 Mercedes-Benz CLS-Class · Electrical System · filed with NHTSA Aug 24, 2022 · ODI 11481015
The sunroof locked open during a road trip. I am mechanically inclined, so adding lubricant and driving through a low pressure air front caused the sunroof to shut. Had I been in an emergency, not mechanically inclined, or if this happen during inclement weather or to a little old lady this would have been a severe issue causing the…
2016 Mercedes-Benz C-Class · Electrical System · filed with NHTSA Feb 19, 2024 · ODI 11572718
In November 2024, the vehicle indicated "add coolant". The vehicle was brought to Mercedes Benz of Scottsdale for servicing. The dealership apparently added coolant without advising me that the B250-E has a 100% chance of failure to the Drive Unit / coolant intrusion unless a small part is replaced before coolant leaks into the…
2017 Mercedes-Benz B-Class Electric Drive · Electrical System · filed with NHTSA Dec 15, 2025 · ODI 11705166
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 group251 other manufacturer communications filed against these Mercedes-Benz models 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 |
|---|---|---|---|
| LI47.70-P-079912 | Service bulletin | Sep 29, 2026 | Complaint Vehicle will not start after DC charging Warning in the instrument cluster related to High‑voltage on board electrical system The… |
| ANN - Tech. Aware. G580e | Other | Sep 21, 2026 | Tech. Awareness: G580e 465.600/465.601 - ISU For Model G580e 465.600/465.601 - Please be aware that initial start up of N147/10n1, N147/10n2… |
| LI54.30-P-080963 | Service bulletin | Sep 17, 2026 | Complaint Issue after OTA Update IC Odometer Reading blank("_ _ _ _") IC Maintanence data unavailable Cause OTA Update E61.0 Remedy In the I… |
| LI54.10-P-080684 | Service bulletin | Sep 17, 2026 | Complaint When disconnecting or connecting the charging connector, the charging socket flashes red and red warning messages are displayed in… |
| 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… |
| NCU - 2026090001 | Service campaign | Sep 11, 2026 | Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the control unit software for… |
| LI54.71-P-079104 | Service bulletin | Sep 11, 2026 | Complaint Traffic sign symbol for "Traffic Sign Assist" is blinking in instrument cluster without obvious cause usually with one of the foll… |
| ANN - MY27 XENTRY Comm. | Other | Sep 11, 2026 | A solution for the XENTRY and MY27 167 communication issue is now available through addon 26.6.1.33608. If after ensuring you've installed l… |
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 LI82.85-P-079271 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 LI82.85-P-079271 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 LI82.85-P-079271 cover?
The manufacturer filed it against 84 model years: 2022 Mercedes-Benz A-Class, 2021 Mercedes-Benz A-Class, 2020 Mercedes-Benz A-Class, 2019 Mercedes-Benz A-Class, 2021 Mercedes-Benz AMG GT, 2020 Mercedes-Benz AMG GT and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.