Check Key Switch Circuit

CAUTION: When the body integrated unit (except for C0 and C5 models) or the immobilizer control module (C0 and C5 models) is replaced, registration of the immobilizer system is required. For details, (Contact an authorized Subaru Dealership)

Wiring diagram:

Immobilizer system Ref. to WIRING DIAGRAM , Immobilizer System.

Fig 1: Key Switch Circuit Diagram

Courtesy of SUBARU OF AMERICA, INC.

Step	Check	Yes	No
1 CHECK POWER SUPPLY CIRCUIT. Disconnect the connector from key warning switch. Measure the voltage between key warning switch connector terminal and chassis ground. Connector & terminal (i63) No. 1 (+) - Chassis ground (-):	Is the voltage 10 V or more?	Go to step 2	Check the harness for an open or short 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. Terminals No. 1 - No. 2:	Is the resistance less than 1 Ω?	Go to step 3	Replace the key warning switch. Ref. to KEY LOCK CYLINDERS
3 CHECK KEY WARNING SWITCH. Remove the ignition key from ignition switch. Measure the resistance between key warning switch connector terminals. Terminals No. 1 - No. 2:	Is the resistance 1 MΩ or more?	Go to step 4	Replace the key warning switch. Ref. to KEY LOCK CYLINDERS
4 CHECK HARNESS BETWEEN KEY WARNING SWITCH AND BODY INTEGRATED UNIT (EXCEPT FOR C0 AND C5 MODELS) OR IMMOBILIZER CONTROL MODULE (C0 AND C5 MODELS). Disconnect the connector from the body integrated unit (except for C0 and C5 models) or the immobilizer control module (C0 and C5 models). Measure the resistance between key warning switch connector terminal and body integrated unit (except for C0 and C5 models) or immobilizer control module (C0 and C5 models) connector terminal. Connector & terminal Body integrated unit (except for C0 and C5 models) (i63) No. 2 - (i84) No. 10: Immobilizer control module (C0 and C5 models) (i63) No. 2 - (i34) No. 3:	Is the resistance less than 10 Ω?	Replace the body integrated unit (except for C0 and C5 models) Ref. to BODY INTEGRATED UNIT . or immobilizer control module (C0 and C5 models) Ref. to IMMOBILIZER CONTROL MODULE	Repair harness between key warning switch and body integrated unit (except for C0 and C5 models) or immobilizer control module (C0 and C5 models).