# 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.

- Type: Service bulletin
- NHTSA id: 11012782
- Published by NHTSA: 2025\-01\-10
- Manufacturer's number: LI54.10\-P\-077250
- Manufacturer's date: 2025\-01\-07
- NHTSA component: ELECTRICAL 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

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2025/MC-11012782-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2025/MC-11012782-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Electrical system

## Trouble codes named

P0A7F

## Vehicles listed

- 2023 to 2024 MERCEDES\-BENZ AMG C43
- 2024 MERCEDES\-BENZ AMG C63 S E
- 2024 MERCEDES\-BENZ AMG GLC43
- 2024 MERCEDES\-BENZ AMG GLC63 S E
- 2022 to 2024 MERCEDES\-BENZ C 300
- 2024 to 2025 MERCEDES\-BENZ E 350
- 2025 MERCEDES\-BENZ E 350 4MATIC
- 2024 MERCEDES\-BENZ E 450
- 2025 MERCEDES\-BENZ E 450 4MATIC
- 2025 MERCEDES\-BENZ E 450 4MATIC ALL\-TERRAIN
- 2023 to 2024 MERCEDES\-BENZ GLC 300
- 2024 MERCEDES\-BENZ GLC 300 COUPE
- 2025 MERCEDES\-BENZ GLC 350 E 4MATIC
- 2021 MERCEDES\-BENZ S 500
- 2023 MERCEDES\-BENZ S 500
- 2022 MERCEDES\-BENZ S 500 4MATIC
- 2024 MERCEDES\-BENZ S 500 4MATIC
- 2021 MERCEDES\-BENZ S 580
- 2023 MERCEDES\-BENZ S 580
- 2022 MERCEDES\-BENZ S 580 4MATIC
- 2024 MERCEDES\-BENZ S 580 4MATIC
- 2023 MERCEDES\-BENZ S 580 E
- 2024 MERCEDES\-BENZ S 580 E 4MATIC
- 2021 MERCEDES\-MAYBACH S 580
- 2022 to 2024 MERCEDES\-MAYBACH S 580 4MATIC
- 2023 to 2024 MERCEDES\-MAYBACH S 680
- 2022 MERCEDES\-MAYBACH S 680 4MATIC

JSON: [/v1/bulletins/11012782](/v1/bulletins/11012782)

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