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

P0A0F

Hybrid Engine Failed to Start

The hybrid control system commanded an internal combustion engine start that did not complete within the expected time. Causes range from low 12V supply to fuel, ignition or starter issues.

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / numberA / 0F

Possible causes

  • Weak 12V auxiliary battery high
  • Starter or ignition system fault medium
  • HV battery state of charge insufficient low

Inspection / repair

  • Difficulty: hard
  • DIY: shop recommended
  • Estimated cost: 200–3000 €
  • Estimated time: 1–6 h
  • Component: hybrid control module
  • Component: engine starter
  • Component: hv battery
  • 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