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Home >> Ford >> 2012 >> Transit Connect Base, Van Cargo >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid) >> DTC Diagnosis >> DTC P0140: O2 Circuit No Activity Detected (Bank 1, Sensor 2)
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DTC P0140: O2 Circuit No Activity Detected (Bank 1, Sensor 2)

P0140 - O2 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/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/fuel ratio is oscillating.
Possible Causes: 
  • HO2S circuit open
  • Damaged HO2S
Diagnostic Aids:  An HO2S 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 .