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

P2447

Secondary Air Injection Pump Stuck On (Bank 2)

Bank 2 secondary air pump runs continuously. Either a stuck-on relay or a shorted control output keeps the pump powered when it should be off.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number4 / 47

Possible causes

  • Relay stuck closed high
  • Driver stage shorted on medium
  • Carbon or debris buildup preventing free movement low

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 80–600 €
  • Estimated time: 0.5–2 h
  • Component: secondary air pump b2
  • Component: secondary air relay
  • 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