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Home >> Ford >> 2017 >> C-Max Energi SE >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Powertrain DTC Charts & Descriptions (Hybrid) >> Diagnostic Trouble Code (DTC) Charts And Descriptions >> P2196 - O2 Sensor Signal Biased/Stuck Rich (Bank 1 Sensor 1)
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P2196 - O2 Sensor Signal Biased/Stuck Rich (Bank 1 Sensor 1)

P2196 - O2 SENSOR SIGNAL BIASED/STUCK RICH (BANK 1 SENSOR 1)

Description:  The universal heated oxygen sensor (HO2S) indicating rich at the end of a test is trying to correct for an over rich condition. This DTC sets when the fuel control system no longer detects switching for a calibrated amount of time.
Possible Causes: 
  • Universal HO2S harness short to voltage
  • Water in the harness connector
  • UO2SPC circuit open
  • Excessive fuel pressure
  • Leaking or contaminated fuel injectors
  • EVAP purge valve stuck open
  • Biased MAP sensor signal
  • Incorrect learned ethanol content
  • Contaminated MAF sensor
  • Leaking positive crankcase ventilation (PCV) system
  • Contaminated oil
  • Oil overfill
  • Camshaft timing
  • Corrosion
  • Incorrect connections
  • Damaged universal HO2S
Diagnostic Aids: 
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to Pinpoint Test H .