P0A80 on Mercedes-Benz: How to Diagnose & Fix
Replace Hybrid Battery Pack
1 Mercedes-Benz model · 1 documented issue · 1 critical
P0A80 on Mercedes-Benz by model: symptoms, diagnosis and fix
Certain EQB high-voltage battery packs built with early-production lithium-ion cells from Farasis Energy (Ganzhou, China) contain cells that are insufficiently robust against stress factors at high state of charge. A deviation in the supplier's production process allows an internal short circuit to develop over time, which can escalate to a thermal event and vehicle fire while parked or driving. Mercedes-Benz has confirmed fire incidents in the US. The campaign has been revised three times: NHTSA 25V050 (Feb 2025, software-only), 25V894 (Dec 2025, BMS software), and finally 26V073 (Feb 2026), which supersedes both and replaces the pack outright. Roughly 11,895 US vehicles built Dec 2021 - May 2024 are covered. Interim guidance is to park outdoors away from structures and charge to no more than 80%.
Common Symptoms
- Recall notice instructing owner to park outdoors
- Charging limited to 80% by dealer or software update
- Battery warning or reduced charge capacity
- Burning smell or smoke in extreme cases
- Reduced usable range after BMS software update
How to Fix
Have the recall performed at a Mercedes-Benz dealer - under 26V073 the entire high-voltage battery is replaced free of charge, even if the vehicle was already 'repaired' under the earlier software-only campaigns 25V050 or 25V894. Until the pack is replaced, cap charging at 80% (set the charge limit in MBUX), avoid leaving the car at high SOC for long periods, and park outside and away from buildings. Check your VIN on nhtsa.gov/recalls, since the phased parts supply means notification dates vary.
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Sources for this issue (4)
- NHTSA Recall 26V073 - Mercedes-Benz EQB High Voltage Battery Fire Risk (recall acknowledgement)article
- NHTSA Recall Report 25V050 - Mercedes-Benz EQB high voltage batteryarticle
- Mercedes Recalls The EQB EV For The Third Time To Try And Stop Battery Firesarticle
- Mercedes-Benz EQB 300 Recalls - Cars.comarticle
P0A80 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0A80 mean on a Mercedes-Benz?
P0A80 stands for "Replace Hybrid Battery Pack." This code appears on hybrid and some electric vehicles and is a direct instruction that the high-voltage hybrid/traction battery pack needs to be replaced because one or more cells or modules have degraded beyond the system's acceptable limits. The battery management system continuously monitors each module's voltage, temperature, and capacity, and when the cells fall too far out of balance or lose too much capacity, it sets this code. You may notice reduced fuel economy, less electric assist, a flashing dashboard battery warning, or the vehicle entering a reduced-power mode. While the code names battery replacement, the true cause is often just one or a few weak modules rather than the whole pack. On Mercedes-Benz it is documented across 1 model: EQB.
What are the most common causes of P0A80?
The most common causes of P0A80 are: Aged or degraded hybrid battery cells/modules losing capacity, One or more weak modules causing cell imbalance, Internal cell resistance increase from heat and age, Poor battery pack cooling (clogged fan/filter, weak coolant pump), Corroded or loose high-voltage bus bar connections, Faulty battery module temperature or voltage sensor, Failed battery management/ECU module misreading cells (less common). The specific cause varies by vehicle.
How much does it cost to fix P0A80 on a Mercedes-Benz?
Repair costs vary widely with the root cause and Mercedes-Benz model; each issue on this page carries its own estimate where one is published.
Looking for P0A80 on a different make?
View P0A80 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.