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Home >> Alfa Romeo >> 2019 >> Giulia Base, AWD >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> 2.0L - DTCS P2AE2-00 To U148C-00 >> DTC Troubleshooting >> P304A-00-Fuel Rail Pressure Sensor 1 - Out Of Range High >> Diagnostic Test

Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. Turn the ignition on.
    2. With the scan tool, read and record DTCs and Freeze Frame data on the repair order.

      Is the DTC active or pending?

      Yes 

      • Go To  2

      No 

  2. CHECK FOR HIGH RESISTANCE IN THE (F851) 5-VOLT SUPPLY CIRCUIT 
    1. Turn the ignition off.
    2. Disconnect the FRPS harness connector.
    3. Disconnected PCM C2 harness connector.
    4. Measure the resistance of the (F851) 5-Volt Supply circuit between the FRPS harness connector and the PCM C2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  3

      No 

      • Repair the high resistance in the (F851) 5-Volt Supply circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  3. CHECK FOR HIGH RESISTANCE IN THE (K179) FUEL RAIL PRESSURE 1 SIGNAL CIRCUIT 
    1. Measure the resistance of the (K179) Fuel Rail Pressure 1 Signal circuit between the FRPS harness connector and the PCM C2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  4

      No 

      • Repair the high resistance in the (K179) Fuel Rail Pressure 1 Signal circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  4. CHECK FOR HIGH RESISTANCE IN THE (K917) SENSOR GROUND CIRCUIT 
    1. Measure the resistance of the (K917) Sensor Ground circuit between the FRPS harness connector and the PCM C2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Replace the Fuel Rail Pressure Sensor in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Repair the high resistance in the (K917) Sensor Ground circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .