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

P01AF

Alternative Fuel Tank A Level Sensor Circuit

Generic electrical fault on alt fuel tank A level sensor.

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number1 / AF

Possible causes

  • Level sensor failed high

Inspection / repair

  • Difficulty: medium
  • DIY: shop recommended
  • Estimated cost: 100–600 €
  • Estimated time: 0.5–3 h
  • Component: alt fuel tank level sensor
  • Component: sensor wiring
  • MIL / check engine light

Sources

References

sae:J2012

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