DTC P0458 Evaporative Emission Control System Purge Control Valve Circuit Low

WARNING: This page is about a different variant/trim than selected.

DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
GENERAL DESCRIPTION < Ref. to DTC P0458 EVAPORATIVE EMISSION CONTROL SYSTEM PURGE CONTROL VALVE CIRCUIT LOW , Diagnostic Trouble Code (DTC) Detecting Criteria. >

TROUBLE SYMPTOM:

Erroneous idling

CAUTION: After repair or replacement of faulty parts, conduct Clear Memory Mode < Ref. to , OPERATION , Clear Memory Mode.> and Inspection Mode < Ref. to , PROCEDURE , Inspection Mode.>.

WIRING DIAGRAM:

Fig 1: DTC P0458 Circuit

Courtesy of SUBARU OF AMERICA, INC.

DTC P0458 DIAGNOSIS

Step	Check	Yes	No
1. CHECK OUTPUT SIGNAL FROM ECM. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B134) No. 14 (+) - Chassis ground (-):	Is the voltage more than 10 V?	Even if malfunction indicator light lights up, the circuit has returned to a normal condition at this time. Contact SOA Service Center.	Go to step 2.
2. CHECK HARNESS BETWEEN PURGE CONTROL SOLENOID VALVE AND ECM CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from purge control solenoid valve and ECM. Measure the resistance of harness between purge control solenoid valve connector and engine ground. Connector & terminal (E4) No. 1 - Engine ground:	Is the resistance more than 1 MΩ?	Go to step 3.	Repair ground short circuit in harness between ECM and purge control solenoid valve connector.
3. CHECK HARNESS BETWEEN PURGE CONTROL SOLENOID VALVE AND ECM CONNECTOR. Measure the resistance of harness between ECM and purge control solenoid valve of harness connector. Connector & terminal (B134) No. 14 - (E4) No. 1:	Is the resistance less than 1 Ω?	Go to step 4.	Repair open circuit in harness between ECM and purge control solenoid valve connector. NOTE: In this case, repair the following: Open circuit in harness between ECM and purge control solenoid valve connector Poor contact in coupling connector
4. CHECK PURGE CONTROL SOLENOID VALVE. Remove the purge control solenoid valve. Measure the resistance between purge control solenoid valve terminals. Terminals No. 1 - No. 2:	Is the resistance 10 -100 Ω?	Go to step 5.	Replace the purge control solenoid valve.< Ref. to PURGE CONTROL SOLENOID VALVE . >
5. CHECK POWER SUPPLY TO PURGE CONTROL SOLENOID VALVE. Turn the ignition switch to ON. Measure the voltage between purge control solenoid valve and engine ground. Connector & terminal (E4) No. 2 (+) - Engine ground (-):	Is the voltage more than 10 V?	Go to step 6.	Repair open circuit in harness between main relay and purge control solenoid valve connector.
6. CHECK POOR CONTACT. Check poor contact in purge control solenoid valve connector.	Is there poor contact in purge control solenoid valve connector?	Repair poor contact in purge control solenoid valve connector.	Contact SOA Service Center.