OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Powertrain generic / SAE

P0A7F

Hybrid Battery Pack Deterioration

The hybrid battery pack capacity or internal resistance has degraded beyond the diagnostic threshold. Performance and fuel economy fall as the pack ages.

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / numberA / 7F

Possible causes

  • Battery pack aged high
  • Cell imbalance in pack medium

Symptoms

  • EV/hybrid system warning light on
  • Reduced power output or limp mode
  • Charging may fail or be slowed
  • Reduced electric range

Inspection / repair

  • Difficulty: shop only
  • DIY: shop recommended
  • Estimated cost: 1500–8000 €
  • Estimated time: 3–12 h
  • Component: hv battery
  • Component: battery energy control module
  • MIL / check engine light
  • emissions-relevant
  • limp mode possible

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication