P0140 – O2 Sensor No Activity (Bank 1 Sensor 2)

Description

The ECM detects no activity from the downstream O2 sensor.

Want to confirm the real cause of this fault code?

A high-quality OBD2 scanner gives you live data, fuel trims, sensor readings and freeze-frame information — exactly what you need to verify the root cause of this code with confidence.

View Recommended Scanners

Symptoms

  • Check engine light
  • Poor fuel economy

Causes

  • Faulty O2 sensor
  • Wiring issues

Diagnosis

  • Monitor O2 data
  • Inspect wiring

Repair

  • Replace O2 sensor
  • Repair wiring