P0A80: Replace Hybrid Battery Pack. What it means
P0A80 is the most common hybrid battery code on Toyota Prius, Camry Hybrid, and Highlander Hybrid. Here's what it actually means and what it costs to fix.
What it means
P0A80 is the OBD-II code Toyota's hybrid system throws when it has measured the battery pack and concluded the pack itself needs replacement. It's not a sensor warning. By the time P0A80 appears, the hybrid ECU has already made the call.
Vehicles where we see this most
- Toyota Prius (all generations)
- Toyota Camry Hybrid
- Toyota Highlander Hybrid
- Lexus CT200h
- Lexus RX400h / RX450h
Most-likely causes
- One or more weak cell modules inside the battery pack. The most common cause and the one P0A80 is specifically designed to flag.
- Cell imbalance: pack still has capacity, but blocks have drifted apart over years of charge/discharge cycles.
- Internal resistance climbing as the nickel-metal-hydride cells age (typical at 8–12 years on a 2nd-gen Prius).
- Rare: a failed BMS or Hybrid Battery ECU misreading a healthy pack. Always rule this out before replacement.
Is it really the battery?
Yes, almost always. P0A80 specifically means the hybrid ECU has decided the pack is the problem. The only thing worth confirming first is whether codes for the Hybrid Battery ECU itself (rather than the pack) are also present. If so, the ECU may need to be ruled out.
What to do next
- Get the codes scanned (free at any auto-parts store) and photograph them, including any sub-codes like P3011–P3030 that point to a specific weak block.
- Take the quiz to see how confident we'd be it's the pack, or call us with your code list and we'll quote you on the phone.
Not sure if this is what's wrong with your car?
Five questions, built by our techs. We'll tell you honestly whether it sounds like the pack, or something cheaper.