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Check Key Warning Switch

Step Check Yes No
1 CHECK DATA MONITOR  .
Using the Subaru Select Monitor, display the data of «key-lock warning SW».
NOTE: For detailed operation procedures, refer to "Application help".
Is the normal input signal displayed when the key is inserted in/removed from the ignition switch? The key warning switch is OK. Go to step .
2 CHECK FUSE  .
Remove and visually check fuse No. 14 (in the main fuse box).
Is the fuse blown out? Replace the fuse with a new part. Go to step .
3 CHECK KEY WARNING SWITCH CIRCUIT  .
  1. Disconnect the connector of body integrated unit.
  2. Insert the key into ignition switch. (LOCK position)
  3. Measure the voltage between the body integrated unit connector and chassis ground.

    Connector & terminal 

    (B280) No. 4 (+) - Chassis ground (-): 

Is the voltage 9 V or more? Go to step . Go to step .
4 CHECK KEY WARNING SWITCH CIRCUIT  .
  1. Remove the key from ignition switch.
  2. Measure the voltage between the body integrated unit connector and chassis ground.

    Connector & terminal 

    (B280) No. 4 (+) - Chassis ground (-): 

Is the voltage less than 1.5 V? The key warning switch is OK. Go to step .
5 CHECK KEY WARNING SWITCH  .
  1. Disconnect the connector of key warning switch.
  2. Insert the key into ignition switch. (LOCK position)
  3. Measure the resistance between key warning switch terminals.

    Terminals 

    No. 1 - No. 2: 

Is the resistance less than 1 Ω? Go to step . Replace the key warning switch.
6 CHECK KEY WARNING SWITCH  .
  1. Remove the key from ignition switch.
  2. Measure the resistance between key warning switch terminals.

    Terminals 

    No. 1 - No. 2: 

Is the resistance 1 MΩ or more? Check the following:
  • Harness for open circuits and shorts between the key warning switch and fuse.
  • Harness for open or short between the body integrated unit and key warning switch.
Replace the key warning switch.