P2203 – NOx Sensor Circuit High

Description

The NOx sensor is reporting a high signal, often caused by wiring faults or sensor contamination.

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Symptoms

  • Poor fuel economy
  • Reduced power
  • Check engine light

Causes

  • Faulty NOx sensor
  • Wiring short to power
  • Exhaust contamination

Diagnosis

  • Check NOx sensor voltage
  • Inspect wiring
  • Check exhaust system

Repair

  • Replace NOx sensor
  • Repair wiring