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Home >> Ford >> 2018 >> Mustang EcoBoost, 2D Convertible, Standard Trans >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid) >> Diagnostic Trouble Code (DTC) Charts and Descriptions >> DTC P0140 - O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 2)
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DTC P0140 - O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 2)

P0140 - O2 SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 1 SENSOR 2)

Description:  If the sensor signal value is not changing from the default value, the PCM commands an oscillating air to fuel ratio attempting to detect some movement in the signal value. This DTC sets when the PCM is unable to detect movement in the sensor signal while the air to fuel ratio is oscillating.
Possible Causes: 
  • HO2S12 circuit open
  • Damaged heated oxygen sensor bank 1, sensor 2 (HO2S12)
Diagnostic Aids:  An O2S12 PID switching across 0.45 volt from 0.2 to 0.9 volts indicates a normal switching HO2S.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST DW .