Subaru Legacy 2003 Service Manual page 4037

DIAGNOSTIC PROCEDURE FOR IMMOBILIZER INDICATOR LIGHT
IMMOBILIZER (DIAGNOSTICS)
1 CHECK IMMOBILIZER INDICATOR LIGHT
COMES ON.
1) Turn ignition switch OFF.
2) Disconnect harness connector from IMM
ECM.
3) Connect a resistor (750 Ω) between IMM
ECM harness connector terminal No. 9 and
chassis ground.
Does indicator light comes on?
2 CHECK IMM ECM GROUND CIRCUIT.
Measure resistance between IMM ECM har-
ness connector terminal and chassis ground.
Connector & terminal
(B141) No. 2, No. 3 — Chassis ground:
Is the measured value less than the specified
value?
3 CHECK IMM ECM IGNITION CIRCUIT.
1) Turn ignition switch ON. (Engine OFF.)
2) Measure voltage between IMM ECM har-
ness connector terminal and chassis
ground.
Connector & terminal
(B141) No. 12 (+) — Chassis ground ( − − − − ):
Does the measured value exceed the spec-
ified value?
4 CHECK IMM ECM POWER SUPPLY CIR-
CUIT.
1) Turn ignition switch OFF.
2) Measure voltage between IMM ECM har-
ness connector terminal and chassis
ground.
Connector & terminal
(B141) No. 10, No. 11 (+) — Chassis
ground ( − − − − ):
Does the measured value exceed the spec-
ified value?
5 CHECK COMBINATION METER CIRCUIT.
1) Remove combination meter. <Ref. to IDI-
14, REMOVAL, Combination Meter Assem-
bly.>
2) Measure voltage between combination
meter harness connector terminal and
chassis ground.
Connector & terminal
H4 non-TURBO model
(i12) No. 7 (+) — Chassis ground ( − − − − ):
H6 and H4 TURBO model
(i10) No. 9 (+) — Chassis ground ( − − − − ):
(i12) No. 1 (+) — Chassis ground ( − − − − ):
Does the measured value exceed the spec-
ified value?
Step Value
Indicator light comes on.
10 Ω
10 V
10 V
10 V
IM-12
Yes
Go to step 2. Go to step 5.
Go to step 3. Repair open circuit
of IMM ECM
ground circuit.
Go to step 4. Check harness for
open or short
between IMM
ECM and ignition
switch.
Replace IMM ECM Check harness for
<Ref. to SL-36, open or short
Immobilizer Con- between IMM
trol Module.>and ECM and fuse.
then replace all
ignition keys
(including the tran-
sponder). Then
perform teaching
operation. Refer to
teaching opera-
tion manual (Pub.
No. S0820GZ).
Go to step 6. Check harness for
open or short
between combina-
tion meter and
fuse.
No