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Home >> Subaru >> 2017 >> WRX STI >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostics) (P2101 To U0423) (2.5L) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P2402 EVAP System Leak Detection Pump Control Circuit High >> Notes
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DTC P2402 EVAP System Leak Detection Pump Control Circuit High: Notes

DTC DETECTING CONDITION: 

Immediately at fault recognition

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 Leak Detection Pump Control Circuit Low Wiring Diagram
G11574326Courtesy of SUBARU OF AMERICA, INC.
Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND LEAK CHECK VALVE ASSEMBLY CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connector from the leak check valve assembly.
  3. Turn the ignition switch to ON.
  4. Measure the voltage between leak check valve assembly and chassis ground.

Connector & terminal 
(R400) No. 4 (+) - Chassis ground (-): 
Is the voltage 10 V or more? Repair the short circuit to power in harness between ECM connector and leak check valve assembly connector. Go to step 2. 
2 CHECK LEAK CHECK VALVE ASSEMBLY. 
  1. Turn the ignition switch to OFF.
  2. Check the vacuum pump of the leak check valve assembly. <Ref. to CHECK VACUUM PUMP , INSPECTION, Leak Check Valve Assembly.>
Is the check result OK? Repair the poor contact in the leak check valve assembly connector. Replace the leak check valve assembly. <Ref. to Leak Check Valve Assembly .>