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Test C3 - Fuel Pressure Regulator Control (PRC)

Fig 1: PRC Sensor Circuit
G90G09225
NOTE: Enter this test only when a Code 25 is displayed during the QUICK TEST procedure or when directed here from another CIRCUIT TEST.
PRC CIRCUIT PIN IDENTIFICATION

Circuit Breakout Box Pin ECA Pin
2.2L MTX Non-Turbo
PRC 11 2T
VPWR 37, 57 1B
2.2L Except MTX Non-Turbo
PRC 21 3M
VPWR 37, 57 1B

1) Checking System Integrity  Visually check all wiring, harnesses, connectors and components for evidence of damage, overheating, shorting or looseness. If a fault is found, repair as necessary. If no faults are found, go to next step.

2) Checking Solenoid Function  Install breakout box and leave ECA disconnected. Turn ignition on. Apply vacuum to fuel pressure regulator. Vacuum should hold. Jumper breakout box PRC test pin to ground. See PRC CIRCUIT PIN IDENTIFICATION  . If vacuum releases, solenoid is functioning okay. Fault is in another circuit or ECA. If vacuum is held, go to step 3.

3) Check Voltage To PRC Solenoid  Disconnect PRC solenoid connector. With ignition on, measure voltage between VPWR (Red/Black) wire and ground. If voltage reading is less than 10 volts, repair VPWR (Red/Black) wire to fuel pump relay. If voltage reading is than 10 volts, go to step 4.

4)  Warm to operating temperature. Turn engine off. Measure voltage between solenoid VPWR and PRC (White/Black) wire while cranking engine. Replace solenoid if voltage is more than 10 volts. If voltage is less than 10 volts, go to next step.

5) PRC Circuit Continuity Check  With breakout box installed and ECA disconnected, remove solenoid connector. Check for continuity between breakout box pin and connector terminal. See PRC CIRCUIT PIN IDENTIFICATION  . If continuity does not exist, repair wire between solenoid connector and ECA.

6)  If continuity is present, check for continuity between PRC breakout box pin and all other test pins. If continuity is found between PRC test pin and another test pin(s), PRC wire is shorted to that circuit. Repair as necessary and recheck circuit. If all circuits are okay, replace ECA.

Fig 2: Probe 2.2L Turbo Fuel Delivery System
G90C09233