Block of codes

P2Bxx codes: NOx limits

This block brings together the codes from P2BAD to P2BAE in the glossary. Open yours to see what it means, its causes and whether you can keep driving.

Reviewed by Daniel Morales, founder of Reprorace SL, on

What this block covers

Emission control

The catalytic converter, oxygen sensors, EGR, fuel vapor system (EVAP), particulate filter and NOx reduction clean the exhaust. A fault here raises pollution and may make the car fail its inspection; left alone, some end in a bigger fault or in limp-home mode.

The 2 codes of the block

  • P2BADNOx limit exceeded: root cause unknown
  • P2BAENOx limit exceeded: NOx control monitoring system

Read your car's fault codes on your phone

With an ECO-LITE in the OBD socket you see the codes in your account, with the data captured when the fault happened, and your workshop can check them remotely, always with your permission.

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