MERCEDES-BENZ, MERCEDES-MAYBACH

LI54.10-P-080199

2026-01-14 · NHTSA 11027656

A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.

Manufacturer summary

Original wording in English

Complaint For the potentially affected vehicles, excessively high aging of the battery was calculated at cold battery temperatures (<10°C) 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 Step 1: Software update of A66 battery module (48 V battery) Step 2: Perform reset routine: 2.1 Read out actual value 056 in A66 control unit (age limit SOH-R) a. If SOH-R <= 125%: Delete fault memory in PTCU control unit (N127) and 48 V battery (A66). Process ended. b. If SOH-R > 125%: Drive for 60 min to add SOH-R value. 2.2 Read out actual value 056 in A66 control unit (age limit SOH-R) a. If SOH-R <= 125%: Delete fault memory in PTCU control unit (N127) and 48 V battery (A66). Process ended. b. If SOH-R > 125%: Park vehicle > 12 hours in the workshop at a warm ambient temperature > 15°C, then drive for 60 min. 2.3 Read out actual value 056 in A66 control unit (age limit SOH-R) a. If SOH-R <= 125%: Delete fault memory in PTCU control unit (N127) and 48 V battery (A66). Process ended. b. If SOH-R > 125%: Create TIPS case

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