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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 P0134 - O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
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DTC P0134 - O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)

P0134 - O2 SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 1 SENSOR 1)

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: 
  • UO2SPC11 circuit open (if equipped)
  • HO2S11 circuit open (if equipped)
  • Deteriorating universal heated oxygen sensor bank 1, sensor 1 (HO2S11) (if equipped)
  • Deteriorating HO2S11 (if equipped)
Diagnostic Aids: 
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
EcoSport 1.5L,
KA
GO to PINPOINT TEST DW .
All others GO to PINPOINT TEST DZ .