{"nhtsa_id":11026020,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2025-12-03","date":"2025-12-03","document_id":"LI54.10-P-078888","mfr_campaign":null,"replaces":null,"component":"ELECTRICAL SYSTEM","mfr_system":null,"summary":"Complaint The check engine light illuminates or the 48 V message is displayed in the instrument cluster Cause Fault code \"P0A7F00\" stored in the 48 V battery G1/3 and/or is current. Remedy 1. Perform software update: In the given problem case, update the software for the control unit G1/3 - 48 V on-board electrical system battery (48V LIB) : --> Remedy SW A0019020424 25/12 2. Carry out SOH reset routine: - Switch on ignition - Read actual value 209 in XENTRY Diagnostics at G1/3 (48 V battery) \"State of Health Capacity-SOHC\" Valid for OBD markets -- If the value is > 80%, no restoration process required -- If the value is < 81%, continue with the following steps Valid for non-OBD markets -- If the value is > 75%, no restoration process required -- If the value is < 76%, continue with the following steps Perform capacity restoration procedure: - Discharge 48 V battery in vehicle with ignition \"On\" and check SOC of 48 V battery in the instrument cluster's workshop menu - For SOC < 25%: Stop unloading and lock the vehicle with the key out of range; (bus idle) - After 1.5 h of bus idle: Charging the 48V battery - When SOC reaches or exceeds 65%, stop charging and lock the vehicle with the key out of range; (bus idle) - After 1.5 h of bus idle: Switch on ignition Read actual value 209 in XENTRY Diagnostics at G1/3 (48 V battery) \"State of Health Capacity-SOHC\" Valid for OBD markets - SOH > 82%: Process is complete and clear fault memory - SOH < 83%: Repeat the steps once more. If the value is still too low after 5 repetitions: Cancel healing process and provide feedback in TIPS case.","document":{"url":"https://static.nhtsa.gov/odi/tsbs/2025/MC-11026020-0001.pdf","alternate_url":"https://static.nhtsa.gov/odi/tsbs/2025/MC-11026020-9999.pdf","confirmed":false},"url":"https://open.wenmarpro.com/bulletins/11026020","components":[{"id":"electrical","name":"Electrical system","parent":null}],"codes":["P0A7F"],"topics":[],"vehicles":[{"make":"MERCEDES-BENZ","model":"AMG CLA35","year_from":2020,"year_to":2024,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG CLA35 4MATIC","year_from":2026,"year_to":2026,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG CLA45","year_from":2014,"year_to":2024,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG CLA45S 4MATIC+","year_from":2026,"year_to":2026,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG GLA 35","year_from":2024,"year_to":2025,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG GLA 35 4MATIC","year_from":2024,"year_to":2024,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG GLA 35 4MATIC","year_from":2026,"year_to":2026,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG GLA35","year_from":2021,"year_to":2023,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG GLA45","year_from":2021,"year_to":2023,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG GLB35","year_from":2021,"year_to":2025,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG GLB35 4MATIC","year_from":2026,"year_to":2026,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"CLA 250","year_from":2018,"year_to":2026,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"CLA 250 4MATIC","year_from":2026,"year_to":2026,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"CLA250","year_from":2014,"year_to":2017,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"GLA 250","year_from":2021,"year_to":2026,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"GLA 250 4MATIC","year_from":2024,"year_to":2024,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"GLA 250 4MATIC","year_from":2026,"year_to":2026,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"GLB 250","year_from":2020,"year_to":2026,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"GLB 250 4MATIC","year_from":2026,"year_to":2026,"match":null,"vehicle_ids":[]}],"as_of":"2026-10-19","note":"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.","attribution":[]}