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Home >> Ford >> 2012 >> Transit Connect Base, Van Cargo >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid) >> DTC Diagnosis >> DTC P2195: O2 Sensor Signal Biased/Stuck Lean - Bank 1, Sensor 1
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DTC P2195: O2 Sensor Signal Biased/Stuck Lean - Bank 1, Sensor 1

P2195 - O2 SENSOR SIGNAL BIASED/STUCK LEAN - BANK 1, SENSOR 1

Description:  A heated oxygen sensor (HO2S) indicating lean 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:  Electrical:
  • HO2S harness short to voltage
  • Water in the harness connector
  • HO2S circuit open
  • UO2SPC circuit open
  • Corrosion
  • Incorrect connections
  • Damaged HO2S
  • Damaged PCM

Fuel System:
  • Excessive fuel pressure
  • Leaking or contaminated fuel injectors
  • Leaking fuel pressure regulator
  • Low fuel pressure or running out of fuel

Evaporative Emission (EVAP) system:
  • EVAP purge valve stuck open

  • Air leaks after the mass airflow (MAF) sensor
  • Vacuum leaks
  • Positive crankcase ventilation (PCV) system is leaking or the valve is stuck open
  • Incorrectly seated engine oil dipstick

Exhaust Gas Recirculation (EGR) System:
  • Leaking gasket
  • Stuck EGR valve
  • Leaking diaphragm or EGR vacuum regulator

Base Engine:
  • Oil overfill
  • Camshaft timing
  • Cylinder compression
  • Exhaust leaks before or near the HO2S
Diagnostic Aids: 
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST H .