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

P2437

AIR System Air Flow or Pressure Sensor Circuit Low Bank 2

A general circuit fault on the secondary air injection (AIR) system flow or pressure sensor on bank 2 - the sensor that verifies air pump flow during cold-start enrichment compensation.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number4 / 37

Possible causes

  • Signal shorted to ground high
  • Connector pins corroded - high contact resistance low
  • Harness chafing through insulation low

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 120–450 €
  • Estimated time: 0.6–2 h
  • Component: air system flow sensor b2
  • MIL / check engine light
  • emissions-relevant

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