Mercedes-Benz bulletin LI54.10-P-080602
What it saysComplaint 48V battery (A66) part numbers A 000 982 78 24, A 000 982 57 30, A 000 982 88 31, A 000 982 50 32, A 000 982 87 32) may trigger a fault message ("48 V Service Required" with fault codes P0ADA91, P0ADE91… NHTSA’s full summary ↓
Mercedes-Benz filed this with NHTSA as a service bulletin dated May 20, 2026, received May 21, 2026, about the electrical system. It names 34 model years (2021–2026). 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.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationComplaint 48V battery (A66) part numbers A 000 982 78 24, A 000 982 57 30, A 000 982 88 31, A 000 982 50 32, A 000 982 87 32) may trigger a fault message ("48 V Service Required" with fault codes P0ADA91, P0ADE91, P0AA100, P0ADD00 or P0AA000) in the instrument cluster. This fault message may prevent the 48 V battery contactors from opening automatically if the 12 V power supply is interrupted. In this case, the 48 V on-board electrical system, including connected components, remain energized. Cause The contactors of the 48 V battery do not open, resulting in residual voltage (> 3V) even when the 12 V battery is disconnected. Remedy When working on the 48 V on-board electrical system or connected components, ensure the component being repaired is de-energized in the 48 V system after disconnecting the 12 V ground line. Use a DVOM and ensure that there is less than 3V across the 48V terminals. • If the voltage is less than 3V, the repair can be continued in accordance with the WIS documentation. • If the voltage is greater than 3V, disconnect the ground line from the 48 V on-board electrical system battery and secure from contacting any ground points of the vehicle before continuing the repair. Once the work has been completed, follow the procedure for clearing the 48 V battery fault message as specified.
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| LI54.10-P-080602 | Service bulletin | May 20, 2026 | 11032890 | PDF, 37 KB |
What the document itself lists
Parts the bulletin names
| Part number | Description | Qty | Find it |
|---|---|---|---|
| A 000 982 78 24 | — | — | |
| A 000 982 57 30 | — | — | |
| A 000 982 88 31 | — | — | |
| A 000 982 50 32 | — | — |
Read by machine from the document NHTSA serves (2 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 themAlso filed against model years this site has no page for: 2024 Mercedes-Benz AMG C63 S E; 2024 Mercedes-Benz AMG C63 S E 4MATIC+; 2026 Mercedes-Benz AMG GT63 S E Performance 4MATIC+; 2024 Mercedes-Benz AMG S 63 E 4MATIC+; 2026 Mercedes-Benz E53 E 4MATIC+ ALL-Terrain.
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 29 model years this bulletin names have filed 387 complaints with NHTSA since 2015. 143 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.
My mom and I were in her car brand new Mercedes adaptive cruise was on the car started to act up with all the warning lights again, which shut all safety systems down air back seatbelts, adaptive cruise, Tronics and the engine wall between 18 wheeler and the freeway wall slammed the vehicle into the freeway hall causing about $5000 worth…
2023 Mercedes-Benz SL-Class · Electrical System · filed with NHTSA Jan 21, 2025 · ODI 11637467
While driving, the driver screen went black and became inoperable. This screen provides the speedometer, tachometer, fuel levels and other critical driving information. It was unsafe because I could not identify the speed at which I was driving - but was able to partially remedy the issue by using the heads up display which depicts the…
2025 Mercedes-Benz CLE-Class · Electrical System · filed with NHTSA Oct 5, 2026 · ODI 11769174
The contact owns a 2025 Mercedes-Benz AMG. The contact stated that while starting the vehicle, the instrument panel became inoperable. The contact stated that the failure occurred after an over-the-air software update was completed for the instrument panel. The vehicle was taken to the dealer the vehicle was not diagnosed or repaired.
2025 Mercedes-Benz CLE-Class · Electrical System · filed with NHTSA May 29, 2026 · ODI 11740825
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 group211 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… |
| 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… |
| 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… |
| LI54.71-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… |
| 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… |
| LI82.60-P-079747 | Service bulletin | Sep 4, 2026 | Complaint The Apple Music app is no longer available in the head unit apps menu after updating the software of the… |
| NCU - 2026080001 | Service campaign | Aug 15, 2026 | Issue Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain Model Year 2027 S-Class (223 platform) ve… |
| LI82.85-P-079088 | Service bulletin | Aug 14, 2026 | Complaint The following most common complaints may be observed: • Brief connectivity interruptions when using Apple CarPlay over Wi-Fi • Aud… |
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 LI54.10-P-080602 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 LI54.10-P-080602 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 LI54.10-P-080602 cover?
The manufacturer filed it against 34 model years: 2026 Mercedes-Benz AMG GT, 2025 Mercedes-Benz AMG GT, 2024 Mercedes-Benz AMG GT, 2026 Mercedes-Benz C-Class, 2025 Mercedes-Benz C-Class, 2024 Mercedes-Benz C-Class and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.