P0A80 on Mercedes-Benz
Replace Hybrid Battery Pack
P0A80 on Mercedes-Benz vehicles indicates replace hybrid battery pack. Au7o has documented this code across 1 Mercedes-Benz model — most commonly on EQB. 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.
Common Causes of P0A80
- •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)
P0A80 on Mercedes-Benz by Model
Mercedes-Benz EQB(1 issue)
- High-Voltage Battery Cell Defect (Farasis Cells) Causing Internal Short and Fire Risk2022-2024
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%.
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View P0A80 across all makes →Frequently Asked Questions
What does P0A80 mean on 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 specifically, this code is documented across 1 model.
What causes P0A80 on Mercedes-Benz vehicles?▼
Common causes on Mercedes-Benz: 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. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0A80 on a Mercedes-Benz?▼
Repair costs vary widely depending on the root cause and specific Mercedes-Benz model.
Which Mercedes-Benz models have P0A80 documented?▼
Au7o has documented P0A80 on 1 Mercedes-Benz model: EQB.