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P2270 - O2 Sensor Signal Biased/Stuck Lean (Bank 1 Sensor 2)

DTC DESCRIPTION P2270 - O2 SENSOR SIGNAL BIASED/STUCK LEAN (BANK 1 SENSOR 2)

For Bronco Sport, 2.0L Corsair Edge Escape/Kuga, 2.0L Explorer, 2.3L Nautilus Ranger, 2.3L Transit Connect, 2.0L 
Description:  This DTC sets when the heated oxygen sensor bank 1, sensor 2 (HO2S12) signal is less than the calibrated rich value during the current key cycle and, after three consecutive intrusive events, the signal cannot be forced greater than the calibrated rich value.
Possible Causes: 
  • Aftermarket exhaust accessories or performance modifications
  • Ethanol content in the fuel
  • HO2S12 circuit intermittent
  • Damaged HO2S12
Diagnostic Aids:  Check for leaks in the exhaust system. Check for an intermittent HO2S12 signal.
For All Others 
Description:  The heated oxygen sensor bank 1, sensor 2 (HO2S12) is forced rich and lean and monitored by the PCM. This DTC sets when the PCM does not detect the output of the HO2S12 in a calibrated amount of time.
Possible Causes: 
  • Pinched, shorted, and corroded wiring and pins
  • Crossed HO2S12 wires
  • Exhaust leaks
  • Contaminated HO2S12
  • Damaged HO2S12
Diagnostic Aids:   
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
Bronco Sport 2.0L, Corsair, Edge, Escape/Kuga 2.0L, Explorer 2.3L, Nautilus, Ranger 2.3L,
Transit Connect 2.0L
GO to Pinpoint Test DW.
All others GO to Pinpoint Test H.