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Service bulletin LI54.10-P-077250

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id11013190
Published by NHTSA2025-01-29
Manufacturer's numberLI54.10-P-077250
Manufacturer's date2025-01-29
NHTSA componentELECTRICAL SYSTEM

NHTSA's summary

Complaint For the potentially affected vehicles, excessively high aging of the battery was calculated at cold battery temperatures (<50°F) and the MIL activated accordingly, even though there is no corresponding high level of aging physically. In this regard, the fault code P0A7F00 "The age limit of the hybrid/high-voltage battery module has been reached" is displayed in the N127 PTCU control unit and/or A66 battery module control unit (48 V battery). Cause Faulty computation of the age limit of the 48 V battery. Remedy Do not replace any parts!! Step 1: Perform the software update of A66 battery module (48 V battery) After SW has been updated, perform the following reset procedure: Step 1: Read the State of Health Resistance - (SOH-R) Step 2: If SOH-R <=125%: Clear fault memory in PTCU(N127) and 48V battery (A66). Procedure finished. If SOH > 125%: Drive for a duration of 60 minutes to retrain the SOH-R value. Step 3: Read the State of Health Resistance - (SOH-R) If SOH-R <=125%: Clear fault memory in PTCU(N127) and 48V battery (A66). Procedure finished. If SOH > 125%: Park vehicle in Workshop for >12 hours in warm ambient temperature >60F, afterwards drive for a duration of 60 minutes. Step 4: Read the State of Health Resistance - (SOH-R) If SOH-R <=125%: Clear fault memory in PTCU(N127) and 48V battery (A66). Procedure finished. If SOH-R is still >125%, open a TIPS case.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Electrical system

Trouble codes named

P0A7F

Vehicles listed
MERCEDES-BENZ AMG C432023 to 2024
MERCEDES-BENZ AMG C63 S E2024
MERCEDES-BENZ AMG GLC432024
MERCEDES-BENZ AMG GLC63 S E2024
MERCEDES-BENZ C 3002022 to 2024
MERCEDES-BENZ E 3502024 to 2025
MERCEDES-BENZ E 350 4MATIC2025
MERCEDES-BENZ E 4502024
MERCEDES-BENZ E 450 4MATIC2025
MERCEDES-BENZ E 450 4MATIC ALL-TERRAIN2025
MERCEDES-BENZ GLC 3002023 to 2024
MERCEDES-BENZ GLC 300 COUPE2024
MERCEDES-BENZ GLC 350 E 4MATIC2025
MERCEDES-BENZ S 5002021
MERCEDES-BENZ S 5002023
MERCEDES-BENZ S 500 4MATIC2022
MERCEDES-BENZ S 500 4MATIC2024
MERCEDES-BENZ S 5802021
MERCEDES-BENZ S 5802023
MERCEDES-BENZ S 580 4MATIC2022
MERCEDES-BENZ S 580 4MATIC2024
MERCEDES-BENZ S 580 E2023
MERCEDES-BENZ S 580 E 4MATIC2024
MERCEDES-MAYBACH S 5802021
MERCEDES-MAYBACH S 580 4MATIC2022 to 2024
MERCEDES-MAYBACH S 6802023 to 2024
MERCEDES-MAYBACH S 680 4MATIC2022

Listing a model year does not mean every vehicle of it is concerned: the document says which.