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Home >> Ford >> 2015 >> Focus S, Standard Trans, Gas >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid) >> Diagnostic Trouble Code (DTC) Charts and Descriptions >> P2197 - O2 Sensor Signal Biased/Stuck Lean - Bank 2, Sensor 1 - DTC Chart
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P2197 - O2 Sensor Signal Biased/Stuck Lean - Bank 2, Sensor 1 - DTC Chart

P2197 - O2 SENSOR SIGNAL BIASED/STUCK LEAN - BANK 2, SENSOR 1 - DTC CHART

Description:  A universal heated oxygen sensor bank 2, sensor 1 (HO2S21) indicating lean at the end of a test is trying to correct for an over lean condition. This DTC sets when the fuel control system no longer detects switching for a calibrated amount of time.
Possible Causes: 
  • Water in the harness connector
  • UO2SPC21 circuit open
  • Corrosion
  • Incorrect connections
  • Low fuel pressure or running out of fuel
  • EVAP purge valve stuck open
  • Biased MAP sensor signal
  • Incorrect learned ethanol content
  • Air leaks after the mass airflow (MAF) sensor (if equipped)
  • Contaminated MAF sensor (if equipped)
  • Vacuum leaks
  • Positive crankcase ventilation (PCV) system is leaking
  • Incorrectly seated engine oil dipstick
  • Leaking gasket
  • Camshaft timing
  • Exhaust leaks before or near the universal HO2S21
  • Damaged universal HO2S21
  • Damaged PCM
Diagnostic Aids: 
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to Pinpoint Test H .
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