Subaru Forester 2004 - Page 613

IM-13
IMMOBILIZER (DIAGNOSTIC)
Diagnostics Chart for Immobilizer Warning Light
Step Check Yes No
1 CHECK POWER SUPPLY CIRCUIT.
1) Disconnect the harness connector from key
warning switch.
2) Measure the voltage between key warning
switch harness connector terminal and chassis
ground.
Connector & terminal
(B74) No. 2 (+) — Chassis ground ( − ):
Is the voltage more than 10 V? Go to step 2. Check the harness
for open or short
between key warn-
ing switch and
fuse.
2 CHECK KEY WARNING SWITCH.
1) Insert the ignition key to the ignition switch.
(OFF or ACC position)
2) Measure the resistance between key warn-
ing switch connector terminals.
Terminal
No. 1 — No. 2:
Is the resistance less than 1
Ω?
Go to step 3. Replace the key
warning switch.
3 CHECK KEY WARNING SWITCH.
1) Remove the ignition key from the ignition
switch.
2) Measure the resistance between key warn-
ing switch connector terminals.
Terminal
No. 1 — No. 2:
Is the resistance more than
1 MΩ?
Go to step 4. Replace the key
warning switch.
4 CHECK HARNESS BETWEEN KEY WARN-
ING SWITCH AND IMM ECM.
1) Disconnect the harness connector from key
warning switch.
2) Disconnect the harness connector from
IMM ECM.
3) Measure the resistance between key warn-
ing switch harness connector terminal and
IMM ECM harness connector terminal.
Connector & terminal
(B74) No. 1 — (B141) No. 4:
Is the resistance less than 10
Ω?
Replace the IMM
ECM <Ref. to SL-
37, Immobilizer
Control Module.>
and then replace
all ignition keys
(including the tran-
sponder). Then
perform teaching
operation. Refer to
teaching opera-
tion manual (Pub.
No. S0820GZ).
Repair the har-
ness between key
warning switch
and IMM ECM.