Diagnostics with Phenomenon: Inspection: Wiring diagram

Push button start system Ref. to WIRING SYSTEM>Push Button Start System>WIRING DIAGRAM .

Fig 1: Push Button Start System Wiring Diagram

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK FUSE. 

   Check the fuse. Ref. to SECURITY AND LOCKS>Relay and Fuse .

   Is the check result OK?

   • Yes  : Go to 2. 
   • No  : Replace the fuse.
2. CHECK CONNECTOR. 

   Check the engagement of each connector and for any deformation or looseness.

   Is the check result OK?

   • Yes  : Go to 3. 
   • No  : Repair the connector, or replace harness.
3. CHECK WIRING HARNESS. 
   1. Disconnect the keyless access CM connector.
   2. Using a tester, measure the voltage between the keyless access CM connector and chassis ground.

      Connector & terminal 

      (B572) No. 2 (+) - Chassis ground (-):

   Is the voltage between 8 V and 16 V?

   • Yes  : Go to 4. 
   • No  : Repair or replace the open circuit of harness.
4. CHECK WIRING HARNESS (OPEN). 

   Using a tester, check continuity between the keyless access CM connector and chassis ground.

   Connector & terminal 

   (B572) No. 11 - Chassis ground:

   Is there continuity?

   • Yes  : Go to 5. 
   • No  : Repair or replace the open circuit of harness.
5. CHECK ACCESSORY RELAY (PUSH BUTTON START). 

   Check the accessory relay (push button start). Ref. to SECURITY AND LOCKS>Accessory Relay (Push Button Start)>INSPECTION .

   Is the check result OK?

   • Yes  : Go to 6. 
   • No  : Replace the relay.
6. CHECK WIRING HARNESS (OPEN). 
   1. Disconnect the keyless access CM connector and the accessory relay (push button start).
   2. Using a tester, check continuity between the keyless access CM connector and the accessory relay (push button start) connector.

      Connector & terminal 

      (B574) No. 4 - (B426) No. 1:

   Is there continuity?

   • Yes  : Go to 7. 
   • No  : Repair or replace the open circuit of harness.
7. CHECK WIRING HARNESS (OPEN). 

   Using a tester, check continuity between the keyless access CM connector and chassis ground.

   Connector & terminal 

   (B574) No. 4 - Chassis ground:

   Is there continuity?

   • Yes  : Repair or replace the short circuit of the harness.
   • No  : Go to 8. 
8. CHECK KEYLESS ACCESS CM. 
   1. Connect the keyless access CM connector.
   2. Using a tester, measure the voltage between the keyless access CM connector and chassis ground when the ignition is turned from OFF to ON.

      Connector & terminal 

      (B574) No. 4 (+) - Chassis ground (-):

   Did the voltage change from 1 V or less → +B-2 V or more?

   • Yes  : System is normal.
   • No  : Replace the keyless access CM. Ref. to SECURITY AND LOCKS>Keyless Access CM>REMOVAL .