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

P0501

Vehicle Speed Sensor "A" Range/Performance

The VSS signal is present but inconsistent — either values jump implausibly or the sensor reports a speed inconsistent with engine RPM in gear. Often a damaged reluctor ring or a sensor with degraded magnetic response.

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number5 / 01

Possible causes

  • Sensor signal intermittent high
  • Reluctor tooth damaged low
  • Sensor element aged beyond calibration window low

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 80–400 €
  • Estimated time: 0.5–3 h
  • Component: vehicle speed sensor
  • Component: reluctor ring
  • MIL / check engine light
  • emissions-relevant
  • drive cycle required

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