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

P0134 - O2 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/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: 
  • UO2SPC circuit open (if equipped)
  • HO2S circuit open (if equipped)
  • Damaged HO2S
  • Damaged universal HO2S
Diagnostic Aids: 
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
E-Series 6.8L,
Escape 2.5L
Manual
Transmission,
Fiesta,
Fusion 3.5L,
Fusion 2.5L
Manual
Transmission,
MKZ,
Transit Connect
GO to PINPOINT TEST DW .
All others GO to PINPOINT TEST DZ .