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Home >> Kia >> 2017 >> Optima Plug-In Hybrid EX >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnosis (1 Of 3) (PHEV) >> DTC P0091-00: Fuel Pressure Regulator 1 Control Circuit Low >> Wiring Inspection >> Control Circuit Inspection >> Control (Low) Circuit Inspection
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Control (Low) Circuit Inspection

  1. Ignition "OFF".
  2. Refer to FUEL PRESSURE REGULATOR and disconnect Fuel Pressure Regulator connector.
  3. Ignition "ON"
  4. Measure voltage between Pin No. 2 (Low) terminal of Fuel Pressure Regulator harness connector and chassis ground.

    Specification:  Approx. 4.4V

  5. Is the measured value within specification?

    YES 

    NO 

    • Repair open or short in control (High) circuit between Fuel Pressure Regulator and ECM/PCM and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
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