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P2273 - O2 Sensor Signal Biased/Stuck Rich (Bank 2 Sensor 2)

DTC DESCRIPTION P2273 - O2 SENSOR SIGNAL BIASED/STUCK RICH (BANK 2 SENSOR 2)

For Edge, 2.7L F-150, 2.7L Nautilus, 2.7L 
Description:  This DTC sets when the heated oxygen sensor bank 2, sensor 2 (HO2S22) signal is greater than the calibrated lean value during the current key cycle and, after three consecutive intrusive events, the signal cannot be forced less than the calibrated lean value.
Possible Causes: 
  • Aftermarket exhaust accessories or performance modifications
  • Ethanol content in the fuel
  • HO2S22 circuit intermittent
  • Damaged HO2S22
Diagnostic Aids:  Check for leaks in the exhaust system. Check for an intermittent HO2S22 signal.
For All Others 
Description:  The heated oxygen sensor bank 2, sensor 2 (HO2S22) is forced rich and lean and monitored by the PCM. This DTC sets when the PCM does not detect the output of the HO2S22 in a calibrated amount of time.
Possible Causes: 
  • Pinched, shorted, and corroded wiring and pins
  • Crossed HO2S22 wires
  • Exhaust leaks
  • Contaminated HO2S22
  • Damaged HO2S22
Diagnostic Aids:   
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
Edge 2.7L, F-150 2.7L,
Nautilus 2.7L
GO to Pinpoint Test DW.
All others GO to Pinpoint Test H.