Toyota Voxy: High-Voltage Hybrid Battery Pack Degradation (P3000)

The nickel-metal hydride high-voltage battery pack (OEM #G9510-28070 on ZWR80) loses cell capacity over time and through thermal cycling, triggering diagnostic trouble code P3000 (Battery Control System fault). As individual cells weaken or fail, the battery management system reduces available power and fuel economy deteriorates markedly. On higher-mileage examples the system may enter a reduced-power limp mode or refuse to start the hybrid drive.

• Persistent P3000 or P3011–P3019 battery fault codes on OBD scan
• Fuel economy noticeably worse than rated 23–26 km/L combined
• Hybrid battery gauge swings rapidly or shows perpetually low charge
• EV-only mode unavailable at low urban speeds
• Triangle warning lamp and master warning illuminate on dash

1. 1

   Request a hybrid battery state-of-health scan showing individual cell voltages and capacity percentage.

2. 2

   On a test drive, watch for the hybrid battery gauge cycling rapidly between full and empty, or the combustion engine failing to shut off at low speeds where EV-only mode should engage.

3. 3

   Check the battery cooling fan behind the rear seat for dust blockage.

≈A$2,760 to ≈A$7,820 at independent workshop rates, shown as an approximate guide in Australian dollars. That is for this job on its own, not for the car.

An estimate, converted to Australian dollars, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

• “Has the high-voltage battery ever been replaced or reconditioned, and is there documentation?”
• “Has the vehicle had a hybrid system health check at a Toyota dealer or hybrid specialist recently?”
• “Is the battery cooling fan cleaned regularly, and has it ever been replaced?”

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.