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

P2414

O2 Sensor Exhaust Sample Error Bank 1 Sensor 1

Same as P237A but on the upstream sensor B1S1 (pre-catalyst). A drifted or sluggish lambda sensor lets the mixture run lean or rich without correction — fuel economy and emissions suffer immediately.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number4 / 14

Possible causes

  • Sensing element fouled high

Symptoms

  • Check engine light on
  • Increased fuel consumption
  • Possible rough idle or hesitation
  • Failed emissions test

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 120–350 €
  • Estimated time: 0.6–1.5 h
  • Component: oxygen sensor b1s1
  • 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