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Home >> Subaru >> 2015 >> WRX Base >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Anti-Theft System - Security And Locks >> Security System >> Inspection >> Check Ignition Switch Circuit
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Check Ignition Switch Circuit

DIAGNOSTIC PROCEDURE

Step Check Yes No
1 CHECK CURRENT DATA. 
Display the data of «BATT voltage» and «IG power supply voltage» using the Subaru Select Monitor.
NOTE: For detailed procedures, refer to "PC application help for Subaru Select Monitor".
Does the «IG power supply voltage» indicate 0 V when the ignition is OFF, and fall within a range of ±1 V from the «BATT voltage» when the ignition is ON? The ignition switch input circuit is OK. Go to step 2. 
2 CHECK IGNITION SWITCH CIRCUIT. 
  1. Turn the ignition to OFF.
  2. Disconnect the connector of body integrated unit.
  3. Turn the ignition switch to ON.
  4. Measure the voltage between the body integrated unit connector and chassis ground.

    Connector & terminal 

    (B281) No. 3 (+) - Chassis ground (-): 

Is the voltage 10 V or more? Check body integrated unit. <Ref. to BASIC DIAGNOSTIC PROCEDURE .> Check the harness for open or short circuit between body integrated unit and fuse.