Check Key Switch Circuit: Wiring Diagram

WARNING: This page is about a different car, the 2011 Subaru Tribeca. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Key Switch - Wiring Diagram

G00514608

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSIS PROCEDURE

Step	Check	Yes	No
1 CHECK POWER SUPPLY CIRCUIT. Disconnect the key warning switch harness connector. Measure the voltage between key warning switch harness connector terminal and chassis ground. Connector & terminal (B350) No. 3 (+) - Chassis ground (-):	Is the voltage 10 V or more?	Go to step 2	Check for an open or short circuit in the harness between the key warning switch and fuse.
2 CHECK KEY WARNING SWITCH. Insert the ignition key in the ignition switch. (OFF or ACC) Measure the resistance between key warning switch connector terminals. Connector & terminal No. 3 - No. 4:	Is the resistance less than 1 Ω?	Go to step 3	Replace the key warning switch.
3 CHECK KEY WARNING SWITCH. Remove the ignition key from the ignition switch. Measure the resistance between key warning switch connector terminals. Connector & terminal No. 3 - No. 4:	Is the resistance 1 MΩ or more?	Go to step 4	Replace the key warning switch.
4 CHECK HARNESS BETWEEN KEY WARNING SWITCH AND BODY INTEGRATED UNIT. Disconnect the key warning switch harness connector. Disconnect the harness connector from the body integrated unit. Measure the resistance between the key warning switch harness connector and body integrated unit harness connector terminals. Connector & terminal (B350) No. 4 - (B281) No. 7:	Is the resistance less than 10 Ω?	Replace the body integrated unit. Ref. to BODY INTEGRATED UNIT . Replace all ignition keys (including the transponder). Execute the registration procedure next. Refer to SUBARU SELECT MONITOR .	Repair the harness between the key warning switch and body integrated unit.