Skip to main content
Diagnose/P0146
P0146Medium SeverityEmissions

O2 Sensor Circuit No Activity (Bank 1, Sensor 3)

What This Means

The third position oxygen sensor on bank 1 (after the secondary catalytic converter) is showing no switching activity and appears non-functional. This sensor is used to monitor catalytic converter efficiency.

Common Symptoms

  • Check engine light on
  • Failed emissions test
  • No driveability change
  • Higher emissions

Common Causes

  • Faulty O2 sensor
  • Damaged wiring or connector
  • Exhaust leak near sensor
  • Catalytic converter degradation
  • PCM circuit failure

Estimated Repair Cost

$150 – $500
Parts and labor (varies by vehicle and location)
Difficulty:Moderate

Need This Fixed?

Find certified mechanics near you who can diagnose and repair P0146.

Find a Shop Near You
Search Another Code

For informational purposes only. Diagnostic trouble codes are starting points for diagnosis, not definitive answers. Always consult a certified mechanic for proper diagnosis and repair. Estimated costs vary by vehicle, location, and shop rates.