Subaru LEGACY 2004 Service Manual page 711

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK BODY INTEGRATED UNIT POWER
SUPPLY CIRCUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the harness connector from
body integrated unit.
3) Measure the voltage between body inte-
grated unit harness connector terminal and
chassis ground.
Connector & terminal
(B280) No. 7 (+) — Chassis ground (
(B281) No. 2 (+) — Chassis ground (
2 CHECK BODY INTEGRATED UNIT POWER
SUPPLY CIRCUIT.
1) Turn the ignition switch to ON. (engine
OFF)
2) Measure the voltage between body inte-
grated unit harness connector terminal and
chassis ground.
Connector & terminal
(i84) No. 1 (+) — Chassis ground (
3 CHECK BODY INTEGRATED UNIT GROUND
CIRCUIT.
1) Turn the ignition switch to OFF.
2) Measure the resistance between body inte-
grated unit harness connector terminal and
chassis ground.
Connector & terminal
(B280) No. 22 — Chassis ground:
(B281) No. 8, No. 9 — Chassis ground:
4 CHECK HARNESS BETWEEN BODY INTE-
GRATED UNIT AND ECM.
1) Disconnect the harness connector from
body integrated unit and ECM.
2) Measure the resistance between body inte-
grated unit harness connector terminal and
ECM connector terminal.
Connector & terminal
2.0 L non-turbo model, 2.5 L KS, KA
model
(B280) No. 18 — (B135) No. 25:
2.0 L turbo model, 3.0 L model, 2.5 L EC,
K4, EK model
(B280) No. 18 — (B137) No. 19:
5 CHECK HARNESS BETWEEN BODY INTE-
GRATED UNIT AND ECM.
Measure the resistance between body inte-
grated unit harness connector terminal and
ECM connector terminal.
Connector & terminal
2.0 L non-turbo model, 2.5 L KS, KA
model
(B280) No. 28 — (B135) No. 33:
2.0 L turbo model, 3.0 L model, 2.5 L EC,
K4, EK model
(B280) No. 28 — (B137) No. 27:
Check
Is the voltage more than 10 V? Go to step 2.
#
):
#
):
Is the voltage more than 10 V? Go to step 3.
#
):
Is the resistance less than 10
"?
Is the resistance less than 10
"?
Is the resistance less than 10
"?
IM(diag)-23
IMMOBILIZER (DIAGNOSTICS)
Yes
Check the harness
for open or short
circuit between
body integrated
unit and fuse.
Check the harness
for open or short
circuit between
body integrated
unit and ignition
switch.
Go to step 4. Repair the open
circuit of body inte-
grated unit ground
circuit.
Go to step 5. Repair the open
circuit of harness
between body inte-
grated unit and
ECM.
Go to step 6. Repair the open
circuit of harness
between body inte-
grated unit and
ECM.
No