Page 1478 of 2453
EN(H6DO)(diag)-317
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK OPERATION OF STARTER MOTOR.
Place the inhibitor switch in “P” or “N” range.
Does the starter motor operate
when ignition switch is turned
to START?
Repair the har-
ness and connec-
tor.
NOTE:In this case, repair
the following item:
•Open or
ground short
circuit of har-
ness between
ECM and start-
er motor con-
nector
•Poor contact
in ECM connec-
tor
Check the starter
motor circuit.
to
EN(H6DO)(diag)-
58, STARTER
MOTOR CIRCUIT,
Diagnostics for
Engine Starting
Fai lu r e.>
Page 1479 of 2453

EN(H6DO)(diag)-318
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
DL:DTC P1560 BACK-UP VOLTAGE CIRCUIT MALFUNCTION
DTC DETECTING CONDITION:
•Immediately at fault recognition
•GENERAL DESCRIPTION
FUNCTION, Diagnostic Trouble Code (DTC) Detecting Criteria.>
CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode
OPERATION, Clear Memory Mode.> and Inspection Mode
Inspection Mode.>.
WIRING DIAGRAM:
EN-03736
SBF-6MAIN SBF
SBF-7
B72
B2A7C23
D7D3D1A5
B5B19
NO.12B47
E2
B21
12
46
53
ECM
EE
36
B134A:
D:B137
B135B:
B136C:
A3
52373634
3412
56
B47
TO OXYGEN SENSOR
NO.13
D2
35
B21
123412131415567816171819910 1120212223 24 25 2627 28 29 3031 32 33
3534 37363938 41404342 4445 47464948 51505352 54
B72
134562
B134
56 7821943102422 23 2511 12 13 14 1526 2728
16 1718 19 20 2133 34293230 31
A:B135
567821943102422 23 2511 12 13 14 1526 2728
16 17 18 1920 2129 30 31 32 33 34 35
B:
B137
5678219431022 2311 12 13 14 1524 2526
16 1718 19 20 2127 28 29 30 31
D:
SBF-5
D6D26
54
MAIN RELAY
BATTERYIGNITIONSWITCH
B136
16101112131415252430
9871718192028212223293231
123456
2726333435
C:
Step Check Yes No
1CHECK INPUT SIGNAL OF ECM.
1) Turn the ignition switch to OFF.
2) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B135) No. 5 (+) — Chassis ground (–):
Is the voltage more than 10 V? Repair poor con-
tact in ECM con-
nector.
Go to step 2.
Page 1480 of 2453
EN(H6DO)(diag)-319
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
2CHECK HARNESS BETWEEN ECM AND
MAIN FUSE BOX CONNECTOR.
1) Disconnect the connectors from ECM.
2) Measure the resistance of harness
between ECM and chassis ground.
Connector & terminal
(B135) No. 5 — Chassis ground:
Is the resistance less than 10
Ω?
Repair the ground
short circuit of har-
ness between
ECM connector
and battery termi-
nal.
Go to step 3.
3CHECK FUSE No. 13.Is the fuse blown out? Replace the fuse. Repair the har-
ness and connec-
tor.
NOTE:In this case, repair
the following item:
•Open circuit
of harness be-
tween ECM and
battery
•Poor contact
in ECM connec-
tor
•Poor contact
of battery termi-
nal
Step Check Yes No
Page 1482 of 2453

EN(H6DO)(diag)-321
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
oil flow control solenoid valve.
3) Measure the resistance between ECM and
oil flow control solenoid valve.
Connector & terminal
(B137) No. 17 — (E67) No. 1:
(B137) No. 16 — (E67) No. 2:
Is the resistance less than 1
Ω?
Go to step 2.Repair the open
circuit of harness
between ECM and
oil flow control
solenoid valve
connector.
NOTE:In this case, repair
the following item:
•Open circuit
of harness be-
tween ECM and
oil flow control
solenoid valve
connector
•Poor contact
of coupling con-
nector
2CHECK OIL FLOW CONTROL SOLENOID
VALVE.
1) Remove the oil flow control solenoid valve
connector.
2) Measure the resistance between oil flow
control solenoid valve terminals.
Te r m i n a l s
No. 1 — No. 2:
Is the resistance between 6 —
12 Ω?
Repair the poor
contact of ECM
and oil flow con-
trol solenoid valve.
Replace the oil
flow control sole-
noid valve.
to ME(H6DO)-77,
Oil Flow Control
Solenoid Valve.>
Page 1484 of 2453

EN(H6DO)(diag)-323
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
oil flow control solenoid valve.
3) Measure the resistance between oil flow
control solenoid valve and engine ground.
Connector & terminal
(E67) No. 1 — Engine ground:
(E67) No. 2 — Engine ground:
Is the resistance more than 1
MΩ?
Go to step 2.Repair the short
circuit between
ECM and oil flow
control solenoid
valve connector.
2CHECK OIL FLOW CONTROL SOLENOID
VALVE.
1) Remove the oil flow control solenoid valve
connector.
2) Measure the resistance between oil flow
control solenoid valve terminals.
Te r m i n a l s
No. 1 — No. 2:
Is the resistance between 6 —
12 Ω?
Repair the poor
contact of ECM
and oil flow con-
trol solenoid valve.
Replace the oil
flow control sole-
noid valve.
to ME(H6DO)-77,
Oil Flow Control
Solenoid Valve.>
Page 1486 of 2453

EN(H6DO)(diag)-325
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
oil flow control solenoid valve.
3) Measure the resistance between ECM and
oil flow control solenoid valve.
Connector & terminal
(B137) No. 15 — (E68) No. 1:
(B137) No. 14 — (E68) No. 2:
Is the resistance less than 1
Ω?
Go to step 2.Repair the open
circuit of harness
between ECM and
oil flow control
solenoid valve
connector.
NOTE:In this case, repair
the following item:
•Open circuit
of harness be-
tween ECM and
oil flow control
solenoid valve
connector
•Poor contact
of coupling con-
nector
2CHECK OIL FLOW CONTROL SOLENOID
VALVE.
1) Remove the oil flow control solenoid valve
connector.
2) Measure the resistance between oil flow
control solenoid valve terminals.
Te r m i n a l s
No. 1 — No. 2:
Is the resistance between 6 —
12 Ω?
Repair the poor
contact of ECM
and oil flow con-
trol solenoid valve.
Replace the oil
flow control sole-
noid valve.
to ME(H6DO)-77,
Oil Flow Control
Solenoid Valve.>
Page 1488 of 2453

EN(H6DO)(diag)-327
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
oil flow control solenoid valve.
3) Measure the resistance between oil flow
control solenoid valve and engine ground.
Connector & terminal
(E68) No. 1 — Engine ground:
(E68) No. 2 — Engine ground:
Is the resistance more than 1
MΩ?
Go to step 2.Repair the short
circuit between
ECM and oil flow
control solenoid
valve connector.
2CHECK OIL FLOW CONTROL SOLENOID
VALVE.
1) Remove the oil flow control solenoid valve
connector.
2) Measure the resistance between oil flow
control solenoid valve terminals.
Te r m i n a l s
No. 1 — No. 2:
Is the resistance between 6 —
12 Ω?
Repair the poor
contact of ECM
and oil flow con-
trol solenoid valve.
Replace the oil
flow control sole-
noid valve.
to ME(H6DO)-77,
Oil Flow Control
Solenoid Valve.>
Page 1492 of 2453

EN(H6DO)(diag)-331
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK ANY OTHER DTC ON DISPLAY.Is any other DTC displayed? Inspect the rele-
vant DTC using
“List of Diagnostic
Tr o u b l e C o d e
(DTC)”.
EN(H6DO)(diag)-
69, List of Diag-
nostic Trouble
Code (DTC).>
Go to step 2.
2CHECK FRONT OXYGEN (A/F) SENSOR DA-
TA.
1) Start the engine.
2) While observing the Subaru Select Monitor
or general scan tool screen, warm-up the
engine until engine coolant temperature is
above 75°C (167°F).
If the engine is already warmed-up, operate at
idle speed for at least 1 minute.
3) Read data of front oxygen (A/F) sensor sig-
nal using the Subaru Select Monitor or general
scan tool.
NOTE:
•Subaru Select Monitor
For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”.
to EN(H6DO)(diag)-26, Subaru Select Moni-
tor.>
•General scan tool
For detailed operation procedure, refer to the
general scan tool operation manual.
Is the measured value within
0.86 — 1.15 at idle?
Go to step 3.Go to step 4.
3CHECK REAR OXYGEN SENSOR SIGNAL.
1) Race engine at speeds from idling to 5,000
rpm for a total of 5 cycles.
NOTE:To increase engine speed to 5,000 rpm, slowly
depress accelerator pedal, taking approximate-
ly 5 seconds, and quickly release accelerator
pedal to decrease engine speed.
2) Operate the LED operation mode for
engine.
NOTE:•Subaru Select Monitor
For detailed operation procedure, refer to the
“LED OPERATION MODE FOR ENGINE”.
Monitor.>
Does the LED of {Rear O2
Rich Signal} blink?
Check front oxy-
gen (A/F) sensor
circuit.
Check rear oxygen
sensor circuit.
FU(H6DO)-30,
Rear Oxygen Sen-
sor.>
4 CHECK EXHAUST SYSTEM.
Check exhaust system parts.
NOTE:Check the following items.
•Looseness of part installation
•Damage (crack, hole etc.) of parts
•Looseness of the front oxygen (A/F) sensor
•Looseness or ill fitting of parts between front
oxygen (A/F) sensor and rear oxygen sensor
Is there any fault in exhaust
system?
Repair or replace
faulty par ts.
Go to step 5.
5CHECK AIR INTAKE SYSTEM.Are there holes, loose bolts or
disconnection of hose on air
intake system?
Repair the air
intake system.
Go to step 6.