LEMON Manuals: Even more car manuals for everyone
Home >> Subaru >> 2017 >> WRX STI >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostics) (P0171 To P0685) (2.5L) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P0459 EVAP System (CPC) Purge Control Valve "A" Circuit High >> Notes

DTC P0459 EVAP System (CPC) Purge Control Valve "A" Circuit High: Notes

DTC DETECTING CONDITION: 

Detected when two consecutive driving cycles with fault occur.

TROUBLE SYMPTOM: 

Improper idling

CAUTION: After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to OPERATION , Clear Memory Mode.>, and Inspection Mode <Ref. to PROCEDURE , Inspection Mode.>.

WIRING DIAGRAM: 

Engine Electrical System <Ref. to WIRING DIAGRAM , Engine Electrical System.>

Fig 1: EVAP System Purge Control Valve A Circuit Low Wiring Diagram
G11574334Courtesy of SUBARU OF AMERICA, INC.
Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND PURGE CONTROL SOLENOID VALVE CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connector from ECM.
  3. Disconnect the connector from the purge control solenoid valve.
  4. Turn the ignition switch to ON.
  5. Measure the voltage between ECM connector and chassis ground.

    Connector & terminal 

    (B137) No. 6 (+) - Chassis ground (-): 

Is the voltage 10 V or more? Repair the short circuit to power in the harness between ECM connector and purge control solenoid valve connector. Go to step .
2 CHECK PURGE CONTROL SOLENOID VALVE. 
  1. Turn the ignition switch to OFF.
  2. Measure the resistance between purge control solenoid valve terminals.

    Terminals 

    No. 1 - No. 2: 

Is the resistance less than 1 Ω? Replace the purge control solenoid valve. <Ref. to Purge Control Solenoid Valve .> Repair the poor contact of ECM connector.