DTC P2270: O2 Sensor Signal Stuck Lean - Bank 1, Sensor 2

2010 Mercury Mariner Hybrid, AWDSECTION DTC P2270: O2 Sensor Signal Stuck Lean - Bank 1, Sensor 2
WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, 2011 Ford Fusion, 2010 Mercury Milan, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
P2270 - O2 SENSOR SIGNAL STUCK LEAN - BANK 1, SENSOR 2

Description:  The downstream heated oxygen sensor (HO2S) is forced rich and lean and monitored by the powertrain control module (PCM). The test fails if the PCM does not detect the output of the HO2S in a calibrated amount of time.
Possible Causes: 
  • Pinched, shorted, and corroded wiring and pins
  • Crossed sensor wires
  • Exhaust leaks
  • Contaminated or damaged sensor
Diagnostic Aids:   
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST H .
RENDER: 1.0x

NO RELATED

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