Subaru Legacy 2002 Service Manual page 3355

DIAGNOSTICS CHART FOR IMMOBILIZER INDICATOR LIGHT
Immobilizer (Diagnostics)
No.
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.
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 (−):
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
(−):
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 (−):
5 CHECK COMBINATION METER CIRCUIT.
1) Remove combination meter. <Ref. to IDI-
15, REMOVAL, Combination Meter Assem-
bly.>
2) Measure voltage between combination
meter harness connector terminal and chassis
ground.
Connector & terminal
4–cylinder engine model:
(i12) No. 7 (+) — Chassis ground (−):
6–cylinder engine model:
(i10) No. 9 (+) — Chassis ground (−):
(i12) No. 1 (+) — Chassis ground (−):
6 CHECK COMBINATION METER CIRCUIT.
Measure resistance between IMM ECM har-
ness connector terminal and combination
meter harness connector terminal.
Connector & terminal
4–cylinder engine model:
(B141) No. 9 — (i12) No. 1:
LHD 6–cylinder engine model:
(B141) No. 9 — (i10) No. 13:
RHD 6–cylinder engine model:
(B141) No. 9 — (i10) No. 7:
Step
Does indicator light comes
on?
Is the resistance less than
10 Ω?
Is the voltage more than 10
V?
Is the voltage more than 10
V?
Is the voltage more than 10
V?
Is the resistance less than
10 Ω?
IM-10
Check Yes
Go to step 2.
Go to step 3.
Go to step 4.
Replace IMM
ECM <Ref. to
SL-35, Immobi-
lizer Control Mod-
ule.> and then
replace all ignition
keys (including
the transponder).
Then perform
teaching opera-
tion. Refer to
teaching operation
manual (Pub. No.
S0820GZ).
Go to step 6.
Faulty LED bulb.
Replace combina-
tion meter printed
circuit. <Ref. to
IDI-16,
DISASSEMBLY,
Combination
Meter Assembly.>
No
Go to step 5.
Repair open cir-
cuit of IMM ECM
ground circuit.
Check harness for
open or short
between IMM
ECM and ignition
switch.
Check harness for
open or short
between IMM
ECM and fuse.
Check harness for
open or short
between combina-
tion meter and
fuse.
Repair harness or
connector.