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Check Ignition Switch Circuit

Step Check Yes No
1 CHECK DATA MONITOR  .
Display the data of «BATT voltage» and «Ignition Power Supply Voltage» using the Subaru Select Monitor.
NOTE: For detailed operation procedures, refer to "Application help".
Does the «Ignition Power Supply Voltage» indicate 0 V when the ignition switch is OFF, and fall within a range of ±1 V from the «BATT voltage» when the ignition switch is ON? The ignition switch input circuit is OK. Go to step .
2 CHECK IGNITION SWITCH CIRCUIT  .
  1. Turn the ignition switch 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.