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

P2444

Secondary Air Injection System Pump Stuck Off (Bank 1)

The secondary-air pump does not run when commanded during cold start. Often a seized pump (after exhaust back-feed corroded the impeller), a blown fuse, or a failed relay.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number4 / 44

Possible causes

  • Pump seized by corrosion high
  • Pump relay failed medium
  • Pump fuse blown medium

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 80–800 €
  • Estimated time: 0.5–3 h
  • Component: secondary air pump
  • Component: secondary air pump relay
  • Component: secondary air pump fuse
  • 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