OBD-II code · Powertrain (generic, extended)

P2202 NOx Sensor Circuit Low (Bank 1)

The NOx sensor signal on bank 1 is below the lower limit. Either short to ground on the analog return, sensor failed at low end, or pump cell stuck.

Is it safe to drive with P2202?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelySignal wire shorted to ground
  • PossibleSensor failed low
  • Less likelyConnector pins corroded - high contact resistance

Symptoms

  • Check engine light or NOx warning on
  • AdBlue/DEF level or quality warning
  • Possible no-start countdown after ignore period
  • Failed emissions inspection (NOx)

Repair at a glance

Difficulty
Medium
DIY friendly
Often, with basic tools
Typical labour
0.5–2.5 h
Emissions test
Likely to fail
After the fix
A drive cycle is needed before the light stays off
Parts involved
Nox Sensor, Nox Sensor Wiring

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.