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Home >> Ford >> 2014 >> Fusion Energi Titanium >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Powertrain DTC Charts & Descriptions (Hybrid) >> DTC Diagnosis >> P2251 - O2 Sensor Negative Current Control Circuit Open - Bank 1, Sensor 1
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P2251 - O2 Sensor Negative Current Control Circuit Open - Bank 1, Sensor 1

P2251 - O2 SENSOR NEGATIVE CURRENT CONTROL CIRCUIT OPEN - BANK 1, SENSOR 1

Description:  This DTC sets when a concern is detected with the circuit used to determine the oxygen content in the exhaust gas.
Possible Causes: 
  • UO2SGREF circuit open
  • Damaged universal heated oxygen sensor (HO2S)
Diagnostic Aids: 
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST DZ: UNIVERSAL HEATED OXYGEN SENSOR (HO2S) .