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

P0512

Starter Request Circuit

The starter request input - the signal that tells the ECU the driver wants to crank the engine - shows a circuit fault. Without it the engine cannot be started under software-managed start strategies (stop-start, push-button, immobiliser-coordinated start).

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number5 / 12

Possible causes

  • Open in switch or harness high

Inspection / repair

  • Difficulty: easy
  • DIY: possible
  • Estimated cost: 60–250 €
  • Estimated time: 0.3–1.2 h
  • Component: starter request input
  • Component: ignition switch
  • MIL / check engine light

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