DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
6
CHECK HARNESS BETWEEN ECM AND
Is the voltage more than
Go to step 7.
Repair harness
THROTTLE POSITION SENSOR CONNEC-
4.5 V?
and connector.
TOR.
NOTE:
1) Turn ignition switch to OFF.
In this case,
2) Disconnect connectors from throttle posi-
repair the follow-
tion sensor.
ing:
3) Turn ignition switch to ON.
• Open circuit in
4) Measure voltage between throttle position
harness between
sensor connector and engine ground.
throttle position
Connector & terminal
sensor and ECM
(E13) No. 1 (+) — Engine ground (-):
connector
• Poor contact in
throttle position
sensor connector
• Poor contact in
ECM connector
• Poor contact in
coupling connec-
tor
• Poor contact in
joint connector
7
CHECK HARNESS BETWEEN ECM AND
Is the resistance less than
Go to step 8.
Repair harness
THROTTLE POSITION SENSOR CONNEC-
1 Q?
and connector.
TOR.
NOTE:
1) Turn ignition switch to OFF.
In this case,
2) Measure resistance of harness between
repair the follow-
ECM connector and throttle position sensor
ing:
connector.
• Open circuit in
Connector & terminal
harness between
(B135) No. 7 — (E13) No. 3:
throttle position
sensor and ECM
connector
• Poor contact in
ECM connector
• Poor contact in
throttle position
sensor connector
• Poor contact in
coupling connec-
tor
8
CHECK HARNESS BETWEEN ECM AND
Is the resistance less than
Repair ground
Go to step 9.
THROTTLE POSITION SENSOR CONNEC-
10 Q?
short circuit in
TOR.
harness between
Measure resistance of harness between
throttle position
throttle position sensor connector and engine
sensor and ECM
ground.
connector.
Connector & terminal
(E13) No. 3 Engine ground:
9
CHECK POOR CONTACT.
Is there poor contact in
Repair poor con-
Replace throttle
Check poor contact in throttle position sensor
throttle position sensor con-
tact in throttle
position sensor.
connector.
nector?
position sensor
<Ref. to
connector.
FU(DOHC
TURBO)-33,
Throttle Position
Sensor.>
EN(DOHC TURBO)-141
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
R: DTC P0123 — THROTTLE POSITION SENSOR CIRCUIT HIGH INPUT —
S088521B21
•  DTC DETECTING CONDITION:
•   Immediately at fault recognition
•  TROUBLE SYMPTOM:
•   Erroneous idling
•   Engine stalls.
•   Poor driving performance
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
  LHD MODEL
for_01_25-23.jpg
EN(DOHC TURBO)-142
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics) • RHD MODEL
for_01_25-24.jpg
EN(DOHC TURBO)-143
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK CURRENT DATA.
Is the value more than 4.9
Go to step 2.
Even if MIL lights
1) Start engine.
V?
up, the circuit has
2) Read data of throttle position sensor signal
returned to a nor-
using Subaru Select Monitor or OBD-II gen-
mal condition at
eral scan tool.
this time. A tem-
NOTE:
porary poor con-
• Subaru Select Monitor
tact of the con-
For detailed operation procedure, refer to the
nector may be the
"READ CURRENT DATA FOR ENGINE".
cause.
<Ref. to EN(DOHC TURBO)-36, Subaru
NOTE:
Select Monitor.>
In this case,
• OBD-II general scan tool
repair the follow-
For detailed operation procedures, refer to the
ing:
OBD-II General Scan Tool Instruction Manual.
• Poor contact in
throttle position
sensor connector
• Poor contact in
ECM connector
• Poor contact in
coupling connec-
tor
2
CHECK HARNESS BETWEEN THROTTLE
Is the resistance less than
Go to step 3.
Repair harness
POSITION SENSOR AND ECM CONNEC-
5Q?
and connector.
TOR.
NOTE:
1) Turn ignition switch to OFF.
In this case,
2) Disconnect connector from throttle position
repair the follow-
sensor.
ing:
3) Measure resistance of harness between
• Open circuit in
throttle position sensor connector and engine
harness between
ground.
throttle position
Connector & terminal
sensor and ECM
(E13) No. 2 Engine ground:
connector
• Poor contact in
coupling connec-
tor
• Poor contact in
joint connector
3
CHECK HARNESS BETWEEN THROTTLE
Is the voltage more than
Repair battery
Replace throttle
POSITION SENSOR AND ECM CONNEC-
4.9 V?
short circuit in
position sensor.
TOR.
harness between
<Ref. to
1) Turn ignition switch to ON.
throttle position
FU(DOHC
2) Measure voltage between throttle position
sensor and ECM
TURBO)-33,
sensor connector and engine ground.
connector. After
Throttle Position
Connector & terminal
repair, replace
Sensor.>
(E13) No. 3 (+) — Engine ground (-):
ECM. <Ref. to
FU(DOHC
TURBO)-47,
Engine Control
Module.>
EN(DOHC TURBO)-144
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics) MEMO:
EN(DOHC TURBO)-145
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
S: DTC P0125 — INSUFFICIENT COOLANT TEMPERATURE FOR CLOSED LOOP FUEL CONTROL —
  DTC DETECTING CONDITION:
•  Two consecutive driving cycles with fault
•  TROUBLE SYMPTOM:
•   Engine would not return to idling.
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
for_01_25-25.jpg
EN(DOHC TURBO)-146
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK ANY OTHER DTC ON DISPLAY.
Does the Subaru Select
Inspect DTC
Go to step 2.
Monitor or OBD-II general
P0117 orP0118
scan tool indicate DTC
using "List of
P0117 or P0118?
Diagnostic
Trouble Code
(DTC)". <Ref. to
EN(DOHC
TURBO)-82, List
of Diagnostic
Trouble Code
(DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0125.
2
CHECK ENGINE COOLING SYSTEM.
Is there a fault in engine
Replace thermo-
Replace engine
NOTE:
cooling system?
stat. <Ref. to
coolant tempera-
Check the following items.
CO-23, Thermo-
ture sensor. <Ref.
• Thermostat open stuck
stat.>
to FU(DOHC
• Coolant level
TURBO)-29,
• Coolant freeze
Engine Coolant
• Tire diameter
Temperature Sen-
sor.>
EN(DOHC TURBO)-147
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
T: DTC P0131 — FRONT OXYGEN (A/F) SENSOR CIRCUIT
RANGE/PERFORMANCE PROBLEM (LOW INPUT) —
S088521B24
NOTE:
For the diagnostic procedure, refer to DTC P0132. <Ref. to EN(DOHCTURBO)-150, DTC P0132 —FRONT OXYGEN (A/F) SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM (HIGH INPUT) —, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
EN(DOHC TURBO)-148
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics) MEMO:
EN(DOHC TURBO)-149
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
U: DTC P0132 — FRONT OXYGEN (A/F) SENSOR CIRCUIT
RANGE/PERFORMANCE PROBLEM (HIGH INPUT) —
S088521B25
DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
• WIRING DIAGRAM:
for_01_25-26.jpg
EN(DOHCTURBO)-150
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK ANY OTHER DTC ON DISPLAY.
Does the Subaru Select Monitor or OBD-II general scan tool indicate DTC P0031, P0032, P1131, P1134 or P1139?
Inspect DTC P0031, P0032, P1131, P1134 or P1139 using "List of Diagnostic Trouble Code (DTC)".<Ref. to EN(DOHC TURBO)-82, List of Diagnostic Trouble Code (DTC).>
Go to step 2.
2
CHECK FRONT (A/F) OXYGEN SENSOR DATA.
1) Start engine. 2) While observing the Subaru Select Monitor or OBD-II general scan tool screen, warm-up the engine until coolant temperature is above 70°C (158°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 signal using Subaru Select Monitor or OBD-II general scan tool. NOTE: • Subaru Select Monitor For detailed operation procedure, refer to the "READ CURRENT DATA FOR ENGINE". <Ref. to EN(DOHC TURBO)-36, Subaru Select Monitor.> • OBD-II general scan tool For detailed operation procedures, refer to the OBD-II General Scan Tool Instruction Manual.
Is the value equal to or more than 0.85 and equal to less than 1.15 in idling?
Go to step 3.
Go to step 4.
3
CHECK 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 approximately 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". <Ref. to EN(DOHC TURBO)-36, Subaru Select Monitor.>
Does the LED of {Rear O2 Rich Signal} blink?
Repair poor con­tact in front oxy­gen (A/F) sensor and rear oxygen sensor connector.
Check rear oxy­gen sensor circuit. <Ref. to FU(DOHC TURBO)-44, Rear Oxygen Sensor.>
4
CHECK EXHAUST SYSTEM.
Check exhaust system parts. NOTE: Check the following items. • Loose installation of portions • Damage (crack, hole etc.) of parts • Looseness of front oxygen (A/F) sensor • Looseness and ill fitting of parts between front oxygen (A/F) sensor and rear oxygen sensor
Is there a fault in exhaust system?
Repair or replace faulty parts.
Replace front oxy­gen (A/F) sensor. <Ref. to FU(DOHC TURBO)-42, Front Oxygen (A/F) Sensor.>
EN(DOHCTURBO)-151
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
V: DTC P0133 — FRONT OXYGEN (A/F) SENSOR CIRCUIT SLOW
RESPONSE —
S088521B26
•  DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
for_01_25-27.jpg
EN(DOHCTURBO)-152
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK ANY OTHER DTC ON DISPLAY.
Does the Subaru Select
Inspect DTC
Go to step 2.
Monitor or OBD-II general
P0031, P0032,
scan tool indicate DTC
P0131, P0132,
P0031, P0032, P0131,
P1130, P1131,
P0132, P1130, P1131,
P1134 orP1139
P1134 or P1139?
using "List of
Diagnostic
Trouble Code
(DTC)". <Ref. to
EN(DOHC
TURBO)-82, List
of Diagnostic
Trouble Code
(DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0133.
2
CHECK EXHAUST SYSTEM.
Is there a fault in exhaust
Repair exhaust
Replace front oxy-
NOTE:
system?
system.
gen (A/F) sensor.
Check the following items.
<Ref. to
• Loose installation of front portion of exhaust
FU(DOHC
pipe onto cylinder heads
TURBO)-42, Front
• Loose connection between front exhaust
Oxygen (A/F)
pipe and front catalytic converter
Sensor.>
• Damage of exhaust pipe resulting in a hole
EN(DOHCTURBO)-153
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
W: DTC P0136 — REAR OXYGEN SENSOR CIRCUIT MALFUNCTION —
S088521B28
•  DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
for_01_25-28.jpg
EN(DOHCTURBO)-154
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK ANY OTHER DTC ON DISPLAY.
Does the Subaru Select Monitor or OBD-II general scan tool indicate DTC P0131 or P0132?
Go to step 2.
Go to step 3.
2
CHECK FAILURE CAUSE OF P0131 or P0132.
Inspect DTC P0131 or P0132 using "List of Diagnostic Trouble Code (DTC)". <Ref. to EN(DOHC TURBO)-82, List of Diagnostic Trouble Code (DTC).>
Is the failure cause of P0131 or P0132 in the fuel system?
Check fuel sys­tem. NOTE: In this case, it is not necessary to inspect DTC P0136.
Go to step 3.
3
CHECK REAR OXYGEN SENSOR DATA.
1) Warm-up the engine until engine coolant temperature is above 70°C (158°F), and keep the engine speed at 2,000 rpm to 3,000 rpm for two minutes. 2) Read data of rear oxygen sensor signal using Subaru Select Monitor or OBD-II gen­eral scan tool. NOTE: • Subaru Select Monitor For detailed operation procedure, refer to the "READ CURRENT DATA SHOWN ON DIS­PLAY FOR ENGINE". <Ref. to EN(DOHC TURBO)-36, Subaru Select Monitor.> • OBD-II general scan tool For detailed operation procedures, refer to the OBD-II General Scan Tool Instruction Manual.
Does the value fluctuate?
Go to step 7.
Go to step 4.
4
CHECK REAR OXYGEN SENSOR DATA.
Read data of rear oxygen sensor signal using Subaru Select Monitor or OBD-II General Scan Tool.
Is the value fixed between 0.2 and 0.4 V?
Go to step 5.
Replace rear oxy­gen sensor. <Ref. to FU(DOHC TURBO)-44, Rear Oxygen Sensor.>
5
CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR.
1) Turn ignition switch to OFF. 2) Disconnect connectors from ECM and rear oxygen sensor. 3) Measure resistance of harness between ECM and rear oxygen sensor connector. Connector & terminal (B135) No. 26 — (B19) No. 4:
Is the resistance more than 3Q?
Repair open cir­cuit in harness between ECM and rear oxygen sensor connector.
Go to step 6.
6
CHECK HARNESS BETWEEN REAR OXY­GEN SENSOR AND ECM CONNECTOR.
1) Turn ignition switch to OFF. 2) Disconnect connector from rear oxygen sensor. 3) Turn ignition switch to ON. 4) Measure voltage between rear oxygen sen­sor harness connector and engine ground or chassis ground. Connector & terminal (B19) No. 3 (+) Engine ground (-):
Is the voltage more than 0.2 V?
Replace rear oxy­gen sensor. <Ref. to FU(DOHC TURBO)-44, Rear Oxygen Sensor.>
Repair harness and connector. NOTE: In this case, repair the follow­ing: • Open circuit in harness between rear oxygen sen­sor and ECM con­nector • Poor contact in rear oxygen sen­sor connector • Poor contact in ECM connector
EN(DOHCTURBO)-155
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
7
CHECK EXHAUST SYSTEM.
Is there a fault in exhaust
Repair or replace
Replace rear oxy-
Check exhaust system parts.
system?
faulty parts.
gen sensor. <Ref.
NOTE:
to FU(DOHC
Check the following items.
TURBO)-44, Rear
• Loose installation of portions
Oxygen Sensor.>
• Damage (crack, hole etc.) of parts
• Looseness and ill fitting of parts between
front oxygen (A/F) sensor and rear oxygen
sensor
EN(DOHCTURBO)-156
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics) MEMO:
EN(DOHCTURBO)-157
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
X: DTC P0139 — REAR OXYGEN SENSOR CIRCUIT SLOW RESPONSE —
S088521B29
•  DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
for_01_25-29.jpg
EN(DOHCTURBO)-158
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK ANY OTHER DTC ON DISPLAY.
Does the Subaru Select
Inspect DTC
Replace rear oxy-
Monitor or OBD-II general
P0136 using "List
gen sensor. <Ref.
scan tool indicate DTC
of Diagnostic
to FU(DOHC
P0136?
Trouble Code
TURBO)-44, Rear
(DTC)". <Ref. to
Oxygen Sensor.>
EN(DOHC
TURBO)-82, List
of Diagnostic
Trouble Code
(DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0139.
EN(DOHCTURBO)-159
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
Y: DTC P0171 — FUEL TRIM MALFUNCTION (A/F TOO LEAN) — s3
NOTE:
For the diagnostic procedure, refer to DTC P0172. <Ref. to EN(DOHC TURBO)-161, DTC P0172 — FUEL
TRIM MALFUNCTION (A/F TOO RICH) —, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
EN(DOHC TURBO)-160
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
Z: DTC P0172 — FUEL TRIM MALFUNCTION (A/F TOO RICH) — S088
  DTC DETECTING CONDITION:
•  Two consecutive driving cycles with fault
•  TROUBLE SYMPTOM:
•   Erroneous idling
•   Engine stalls.
•   Poor driving performance
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
No.
Step
Check
Yes
No
1
CHECK EXHAUST SYSTEM.
Are there holes or loose
Repair exhaust
Go to step 2.
bolts on exhaust system?
system.
2
CHECK AIR INTAKE SYSTEM.
Are there holes, loose bolts
Repair air intake
Go to step 3.
or disconnection of hose on
system.
air intake system?
3
CHECK FUEL PRESSURE.
Is fuel pressure between
Go to step 4.
Repair the follow-
WARNING:
284 and 314 kPa (2.9—
ing items.
• Place "NO FIRE" signs near the working
3.2 kg/cm2, 41 — 46 psi)?
Fuel pressure
area.
too high
• Be careful not to spill fuel on the floor.
• Clogged fuel
1) Release fuel pressure.
return line or bent
(1) Disconnect connector from fuel pump
hose
relay.
Fuel pressure
(2) Start the engine and run it until it stalls.
too low
(3) After the engine stalls, crank it for five
• Improper fuel
more seconds.
pump discharge
(4) Turn ignition switch to OFF.
• Clogged fuel
2) Connect connector to fuel pump relay.
supply line
3) Disconnect fuel delivery hose from fuel
filter, and connect fuel pressure gauge.
4) Install fuel filler cap.
5) Start the engine and idle while gear posi-
tion is neutral.
6) Measure fuel pressure while disconnecting
pressure regulator vacuum hose from intake
manifold.
WARNING:
Before removing fuel pressure gauge,
release fuel pressure.
NOTE:
If fuel pressure does not increase, squeeze
fuel return hose 2 to 3 times, then measure
fuel pressure again.
EN(DOHC TURBO)-161
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
4
CHECK FUEL PRESSURE.
After connecting pressure regulator vacuum hose, measure fuel pressure. WARNING: Before removing fuel pressure gauge, release fuel pressure. NOTE: • If fuel pressure does not increase, squeeze fuel return hose 2 to 3 times, then measure fuel pressure again. • If out of specification as measured at this step, check or replace pressure regulator and pressure regulator vacuum hose.
Is fuel pressure between 206 and 235 kPa (2.1 — 2.4 kg/cm2, 30 — 34 psi)?
Go to step 5.
Repair the follow­ing items. Fuel pressure too high
• Faulty pressure regulator • Clogged fuel return line or bent hose Fuel pressure too low • Faulty pressure regulator • Improper fuel pump discharge • Clogged fuel supply line
5
CHECK ENGINE COOLANT TEMPERA­TURE SENSOR.
1) Start the engine and warm-up completely. 2) Read data of engine coolant temperature sensor signal using Subaru Select Monitor or OBD-II general scan tool. NOTE: • Subaru Select Monitor For detailed operation procedure, refer to the "READ CURRENT DATA FOR ENGINE". <Ref. to EN(DOHC TURBO)-36, Subaru Select Monitor.> • OBD-II general scan tool For detailed operation procedures, refer to the OBD-II General Scan Tool Instruction Manual.
Is temperature greater than 60°C (140°F)?
Go to step 6.
Replace engine coolant tempera­ture sensor. <Ref. to FU(DOHC TURBO)-29, Engine Coolant Temperature Sen­sor.>
6
CHECK INTAKE MANIFOLD PRESSURE SENSOR.
1) Start the engine and warm-up engine until coolant temperature is greater than 60°C (140°F). 2) Place the shift lever in neutral position. 3) Turn A/C switch to OFF. 4) Turn all accessory switches to OFF. 5) Read data of intake manifold pressure sen­sor signal using Subaru Select Monitor or OBD-II general scan tool. NOTE: • Subaru Select Monitor For detailed operation procedure, refer to the "READ CURRENT DATA FOR ENGINE". <Ref. to EN(DOHC TURBO)-36, Subaru Select Monitor.> • OBD-II general scan tool For detailed operation procedure, refer to the OBD-II General Scan Tool Instruction Manual. Specification: • Intake manifold absolute pressure Ignition ON 73.3 — 106.6 kPa (550 — 800 mmHg, 21.65— 31.50 inHg) Idling 24.0 — 41.3 kPa (180 — 310 mmHg, 7.09 — 12.20 inHg)
Is the value within the specifications?
Go to step 7.
Replace mass air flow and intake manifold pressure sensor. <Ref. to FU(DOHC TURBO)-34, Mass Air Flow and Intake Air Tem­perature Sensor.>
EN(DOHC TURBO)-162
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
7
CHECK INTAKE AIR TEMPERATURE SEN-
Is value obtained when
Contact your
Check mass air
SOR.
ambient temperature is
Subaru distributor.
flow and intake air
1) Start the engine and warm-up engine until
subtracted from intake air
NOTE:
temperature sen-
coolant temperature is greater than 60°C
temperature greater than
Inspection by
sor. <Ref. to
(140°F).
-10°C (14°F) and less than
DTM is required,
FU(DOHC
2) Place the shift lever in neutral position.
50°C (122°F)?
because probable
TURBO)-34, Mass
3) Turn A/C switch to OFF.
cause is deterio-
Air Flow and
4) Turn all accessory switches to OFF.
ration of multiple
Intake Air Tem-
5) Open front hood.
parts.
perature Sensor.>
6) Measure ambient temperature.
7) Read data of intake manifold pressure sen-
sor signal using Subaru Select Monitor or
OBD-II general scan tool.
NOTE:
• Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE".
<Ref. to EN(DOHC TURBO)-36, Subaru
Select Monitor.>
• OBD-II general scan tool
For detailed operation procedure, refer to the
OBD-II General Scan Tool Instruction Manual.
EN(DOHC TURBO)-163
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
AA: DTC P0244 — WASTEGATE CONTROL SOLENOID VALVE
MALFUNCTION (HIGH INPUT) —
S088521H65
•  DTC DETECTING CONDITION:
•  Two consecutive driving cycles with fault
•  TROUBLE SYMPTOM:
•   Erroneous idling
•   Engine stalls.
•   Poor driving performance
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
for_01_25-30.jpg
EN(DOHC TURBO)-164
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK ANY OTHER DTC ON DISPLAY.
Does the Subaru Select
Inspect DTC
Replace waste-
Monitor or OBD-II general
P0245 or P0246
gate control sole-
scan tool indicate DTC
using "List of
noid valve. <Ref.
P0245 or P0246?
Diagnostic
to FU(DOHC
Trouble Code
TURBO)-41,
(DTC)". <Ref. to
Wastegate Control
EN(DOHC
Solenoid Valve.>
TURBO)-82, List
of Diagnostic
Trouble Code
(DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0121.
EN(DOHC TURBO)-165
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
AB: DTC P0245 — WASTEGATE CONTROL SOLENOID VALVE CIRCUIT LOW
INP U T S088521H66
•  DTC DETECTING CONDITION:
•   Immediately at fault recognition
•  TROUBLE SYMPTOM:
•   Erroneous idling
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
for_01_25-31.jpg
EN(DOHC TURBO)-166
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK OUTPUT SIGNAL FROM ECM.
Is the voltage more than 10
Even if MIL lights
Go to step 2.
1) Turn ignition switch to ON.
V?
up, the circuit has
2) Measure voltage between ECM and chas-
returned to a nor-
sis ground.
mal condition at
Connector & terminal
this time. Contact
(B137) No. 24 (+) — Chassis ground
with your Subaru
distributor.
NOTE:
Inspection by
DTM is required,
because probable
cause is deterio-
ration of multiple
parts.
2
CHECK HARNESS BETWEEN WASTEGATE
Is the resistance less than
Repair ground
Go to step 3.
CONTROL SOLENOID VALVE AND ECM
10 Q?
short circuit in
CONNECTOR.
harness between
1) Turn ignition switch to OFF.
ECM and waste-
2) Disconnect connectors from wastegate
gate control sole-
control solenoid valve and ECM.
noid valve con-
3) Measure resistance of harness between
nector.
wastegate control solenoid valve connector
and engine ground.
Connector & terminal
(B127) No. 1 Engine ground:
3
CHECK HARNESS BETWEEN WASTEGATE
Is the resistance less than
Go to step 4.
Repair open cir-
CONTROL SOLENOID VALVE AND ECM
1 Q?
cuit in harness
CONNECTOR.
between ECM
Measure resistance of harness between ECM
and wastegate
and wastegate control solenoid valve of har-
control solenoid
ness connector.
valve connector.
Connector & terminal
NOTE:
(B137) No. 24 — (B127) No. 1:
In this case,
repair the follow-
ing:
• Open circuit in
harness between
ECM and waste-
gate control sole-
noid valve con-
nector
4
CHECK WASTEGATE CONTROL SOLE-
Is the resistance between
Go to step 5.
Replace waste-
NOID VALVE.
30 and 34 Q?
gate control sole-
1) Remove wastegate control solenoid valve.
noid valve. <Ref.
2) Measure resistance between purge control
to FU(DOHC
solenoid valve terminals.
TURBO)-41,
Terminals
Wastegate Control
No. 1 — No. 2:
Solenoid Valve.>
5
CHECK POWER SUPPLY TO WASTEGATE
Is the voltage more than 10
Go to step 6.
Repair open cir-
CONTROL SOLENOID VALVE.
V?
cuit in harness
1) Turn ignition switch to ON.
between main
2) Measure voltage between wastegate con-
relay and waste-
trol solenoid valve and engine ground.
gate control sole-
Connector & terminal
noid valve con-
(B127) No. 2 (+) — Engine ground (-):
nector.
EN(DOHC TURBO)-167
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
6
CHECK POOR CONTACT.
Is there poor contact in
Repair poor con-
Contact your
Check poor contact in wastegate control solen
wastegate control solenoid
tact in wastegate
Subaru distributor.
noid valve connector.
valve connector?
control solenoid
NOTE:
valve connector.
Inspection by
DTM is required,
because probable
cause is deterio-
ration of multiple
parts.
EN(DOHC TURBO)-168
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics) MEMO:
EN(DOHC TURBO)-169
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
AC: DTC P0246 — WASTEGATE CONTROL SOLENOID VALVE CIRCUIT HIGH
INP U T S088521H67
•  DTC DETECTING CONDITION:
•   Immediately at fault recognition
•  TROUBLE SYMPTOM:
•   Erroneous idling
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
for_01_25-32.jpg
EN(DOHC TURBO)-170
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK OUTPUT SIGNAL FROM ECM.
Is the voltage more than 10
Go to step 3.
Go to step 2.
1) Turn ignition switch to ON.
V?
2) Measure voltage between ECM and chas-
sis ground.
Connector & terminal
(B137) No. 24 (+) — Chassis ground
2
CHECK POOR CONTACT.
Is there poor contact in
Repair poor con-
Replace ECM.
Check poor contact in ECM connector.
ECM connector?
tact in ECM con-
<Ref. to
nector.
FU(DOHC
TURBO)-47,
Engine Control
Module.>
3
CHECK HARNESS BETWEEN WASTEGATE
Is the voltage more than 10
Repair battery
Go to step 4.
CONTROL SOLENOID VALVE AND ECM
V?
short circuit in
CONNECTOR.
harness between
1) Turn ignition switch to OFF.
ECM and waste-
2) Disconnect connector from wastegate con-
gate control sole-
trol solenoid valve.
noid valve con-
3) Turn ignition switch to ON.
nector. After
4) Measure voltage between ECM and chas-
repair, replace
sis ground.
ECM. <Ref. to
Connector & terminal
FU(DOHC
(B137) No. 24 (+) — Chassis ground
TURBO)-47,
(-):
Engine Control
Module.>
4
CHECK WASTEGATE CONTROL SOLE-
Is the resistance less than
Replace waste-
Go to step 5.
NOID VALVE.
1 Q?
gate control sole-
1) Turn ignition switch to OFF.
noid valve <Ref.
2) Measure resistance between wastegate
to FU(DOHC
control solenoid valve terminals.
TURBO)-41,
Terminals
Wastegate Control
No. 1 — No. 2:
Solenoid Valve.>
and ECM <Ref. to
FU(DOHC
TURBO)-47,
Engine Control
Module.>
5
CHECK POOR CONTACT.
Is there poor contact in
Repair poor con-
Replace ECM.
Check poor contact in ECM connector.
ECM connector?
tact in ECM con-
<Ref. to
nector.
FU(DOHC
TURBO)-47,
Engine Control
Module.>
EN(DOHC TURBO)-171
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
AD: DTC P0301 — CYLINDER 1 MISFIRE DETECTED — S088
NOTE:
For the diagnostic procedure, refer to DTC P0304. <Ref. to EN(DOHC TURBO)-172, DTC P0304 — CYL­INDER 4 MISFIRE DETECTED —, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
AE: DTC P0302 — CYLINDER 2 MISFIRE DETECTED — S088
NOTE:
For the diagnostic procedure, refer to DTC P0304. <Ref. to EN(DOHC TURBO)-172, DTC P0304 — CYL­INDER 4 MISFIRE DETECTED —, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
AF: DTC P0303 — CYLINDER 3 MISFIRE DETECTED — S088521B39
NOTE:
For the diagnostic procedure, refer to DTC P0304. <Ref. to EN(DOHC TURBO)-172, DTC P0304 — CYL­INDER 4 MISFIRE DETECTED —, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>
AG: DTC P0304 — CYLINDER 4 MISFIRE DETECTED —
S088521B40
•  DTC DETECTING CONDITION:
•  Two consecutive driving cycles with fault
•   Immediately at fault recognition (A misfire which could damage catalyst occurs.)
•  TROUBLE SYMPTOM:
•   Engine stalls.
•   Erroneous idling
•   Rough driving
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode < Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
EN(DOHC TURBO)-172
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
•  WIRING DIAGRAM:
•  LHD MODEL
for_01_25-33.jpg
S2M2186
EN(DOHC TURBO)-173
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics) • RHD MODEL
for_01_25-34.jpg
EN(DOHC TURBO)-174
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK ANY OTHER DTC ON DISPLAY.
Does the Subaru Select Monitor or OBD-II general scan tool indicate DTC P0106, P0107, P0108, P0117, P0118or P0125?
Inspect DTC P0106, P0107, P0108, P0117, P0118 orP0125 using "List of Diagnostic Trouble Code (DTC)". <Ref. to EN(DOHC TURBO)-82, List of Diagnostic Trouble Code (DTC).> NOTE: In this case, it is not necessary to inspect DTC P0301, P0302, P0303 and P0304.
Go to step 2.
2
CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to ON. 2) Measure voltage between ECM connector and chassis ground on faulty cylinders. Connector & terminal #1 (B137) No. 1 (+) — Chassis ground
#2 (B136) No. 6 (+) — Chassis ground #3 (B136) No. 5 (+) — Chassis ground #4 (B136) No. 4 (+) — Chassis ground
Is the voltage more than 10 V?
Go to step 7.
Go to step 3.
3
CHECK HARNESS BETWEEN FUEL INJEC­TOR AND ECM CONNECTOR.
1) Turn ignition switch to OFF. 2) Disconnect connector from fuel injector on faulty cylinders. 3) Disconnect connector from ECM. 4) Measure voltage between ECM connector and engine ground on faulty cylinders. Connector & terminal #1 (E5) No. 1 Engine ground: #2 (E16) No. 1 Engine ground: #3 (E6) No. 1 — Engine ground: #4 (E17) No. 1 Engine ground:
Is the resistance less than 10 Q?
Repair ground short circuit in harness between fuel injector and ECM connector.
Go to step 4.
4
CHECK HARNESS BETWEEN FUEL INJEC­TOR AND ECM CONNECTOR.
Measure resistance of harness connector between ECM connector and fuel injector on faulty cylinders. Connector & terminal #1 (B137) No. 1 — (E5) No. 1: #2 (B136) No. 6 — (E16) No. 1: #3 (B136) No. 5 — (E6) No. 1: #4 (B136) No. 4 — (E17) No. 1:
Is the resistance less than 1 Q?
Go to step 5.
Repair harness and connector. NOTE: In this case, repair the follow­ing: • Open circuit in harness between ECM and fuel injector connector • Poor contact in coupling connec­tor
EN(DOHC TURBO)-175
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
5
CHECK FUEL INJECTOR.
Is the resistance between 5
Go to step 6.
Replace faulty
Measure resistance between fuel injector ter-
and 20 Q?
fuel injector. <Ref.
minals on faulty cylinder.
to FU(DOHC
Terminals
TURBO)-37, Fuel
No. 1 — No. 2:
Injector.>
6
CHECK POWER SUPPLY LINE.
Is the voltage more than 10
Repair poor con-
Repair harness
1) Turn ignition switch to ON.
V?
tact in all connec-
and connector.
2) Measure voltage between fuel injector and
tors in fuel injector
NOTE:
engine ground on faulty cylinders.
circuit.
In this case,
Connector & terminal
repair the follow-
#1 (E5) No. 2 (+) — Engine ground (-):
ing:
#2 (E16) No. 2 (+) — Engine ground
• Open circuit in
(-)'¦
harness between
#3 (E6) No. 2 (+) — Engine ground (-):
main relay and
#4 (E17) No. 2 (+) — Engine ground
fuel injector con-
(-)¦'
nector on faulty
cylinders
• Poor contact in
coupling connec-
tor
• Poor contact in
main relay con-
nector
• Poor contact in
fuel injector con-
nector on faulty
cylinders
7
CHECK HARNESS BETWEEN FUEL INJEC-
Is the voltage more than 10
Repair battery
Go to step 8.
TOR AND ECM CONNECTOR.
V?
short circuit in
1) Turn ignition switch to OFF.
harness between
2) Disconnect connector from fuel injector on
ECM and fuel
faulty cylinder.
injector. After
3) Turn ignition switch to ON.
repair, replace
4) Measure voltage between ECM connector
ECM. <Ref. to
and chassis ground on faulty cylinders.
FU(DOHC
Connector & terminal
TURBO)-47,
#1 (B137) No. 1 (+) — Chassis ground
Engine Control
(-)¦'
Module.>
#2 (B136) No. 6 (+) — Chassis ground
#3 (B136) No. 5 (+) — Chassis ground
#4 (B136) No. 4 (+) — Chassis ground
8
CHECK FUEL INJECTOR.
Is the resistance less than
Replace faulty
Go to step 9.
1) Turn ignition switch to OFF.
1 Q?
fuel injector <Ref.
2) Measure resistance between fuel injector
to FU(DOHC
terminals on faulty cylinder.
TURBO)-37, Fuel
Terminals
Injector.> and
No. 1 — No. 2:
ECM <Ref. to
FU(DOHC
TURBO)-47,
Engine Control
Module.>
9
CHECK INSTALLATION OF CAMSHAFT
Is camshaft position sensor
Tighten camshaft
Go to step 10.
POSITION SENSOR/CRANKSHAFT POSI-
or crankshaft position sen-
position sensor or
TION SENSOR.
sor loosely installed?
crankshaft posi-
tion sensor.
EN(DOHC TURBO)-176
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
10
CHECK CRANKSHAFT SPROCKET.
Remove timing belt cover.
Is crankshaft sprocket rusted or does it have bro­ken teeth?
Replace crank­shaft sprocket. <Ref. to ME(DOHC TURBO)-57, Crankshaft Sprocket.>
Go to step 11.
11
CHECK INSTALLATION CONDITION OF TIMING BELT.
Turn crankshaft using ST, and align alignment mark on crankshaft sprocket with alignment mark on cylinder block. ST 499987500 CRANKSHAFT SOCKET
Is timing belt dislocated from its proper position?
Repair installation condition of timing belt. <Ref. to ME(DOHC TURBO)-48, Tim­ing Belt Assem­bly. >
Go to step 12.
12
CHECK FUEL LEVEL.
Is the fuel meter indication higher than the "Lower" level?
Go to step 13.
Replenish fuel so fuel meter indica­tion is higher than the "Lower" level. After replenishing fuel, Go to step 13.
13
CHECK STATUS OF CHECK ENGINE MAL­FUNCTION INDICATOR LAMP (MIL).
1) Clear memory using Subaru Select Moni­tor. <Ref. to EN(DOHC TURBO)-47, Clear Memory Mode.> 2) Start engine, and drive the vehicle more than 10 minutes.
Is the MIL coming on or blinking?
Go to step 15.
Go to step 14.
14
CHECK CAUSE OF MISFIRE DIAGNOSED.
Was the cause of misfire diagnosed when the engine is running?
Finish diagnostics operation, if the engine has no abnormality. NOTE: Ex. Remove spark plug cord, etc.
Repair poor con­tact. NOTE: In this case, repair the follow­ing: • Poor contact in ignitor connector • Poor contact in ignition coil con­nector • Poor contact in fuel injector con­nector on faulty cylinders • Poor contact in ECM connector • Poor contact in coupling connec­tor
EN(DOHC TURBO)-177
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
15
CHECK AIR INTAKE SYSTEM.
Is there a fault in air intake system?
Repair air intake system. NOTE: Check the follow­ing items: • Are there air leaks or air suc­tion caused by loose or dislo­cated nuts and bolts? • Are there cracks or any dis­connection of hoses?
Go to step 16.
16
CHECK MISFIRE SYMPTOM.
1) Turn ignition switch to ON. 2) Read diagnostic trouble code (DTC). • Subaru Select Monitor <Ref. to EN(DOHC TURBO)-36, Subaru Select Monitor.> • OBD-II general scan tool For detailed operation procedures, refer to the OBD-II General Scan Tool Operation Manual. NOTE: Perform diagnosis according to the items listed below.
Does the Subaru Select Monitor or OBD-II general scan tool indicate only one DTC?
Go to step 21.
Go to step 17.
17
CHECK DIAGNOSTIC TROUBLE CODE (DTC) ON DISPLAY.
Does the Subaru Select Monitor or OBD-II general scan tool indicate DTC P0301 and P0302?
Go to step 22.
Go to step 18.
18
CHECK DIAGNOSTIC TROUBLE CODE (DTC) ON DISPLAY.
Does the Subaru Select Monitor or OBD-II general scan tool indicate DTC P0303 and P0304?
Go to step 23.
Go to step 19.
19
CHECK DIAGNOSTIC TROUBLE CODE (DTC) ON DISPLAY.
Does the Subaru Select Monitor or OBD-II general scan tool indicate DTC P0301 and P0303?
Go to step 24.
Go to step 20.
20
CHECK DIAGNOSTIC TROUBLE CODE (DTC) ON DISPLAY.
Does the Subaru Select Monitor or OBD-II general scan tool indicate DTC P0302 and P0304?
Go to step 25.
Go to step 26.
21
ONLY ONE CYLINDER
Is there a fault in that cylin­der?
Repair or replace faulty parts. NOTE: Check the follow­ing items. • Spark plug • Fuel injector • Compression ratio
Goto DTC P0171 and P0172. <Ref. to EN(DOHC TURBO)-160, DTC P0171 -FUEL TRIM MAL­FUNCTION (A/F TOO LEAN) -, Diagnostic Proce­dure with Diag­nostic Trouble Code (DTC).>
EN(DOHC TURBO)-178
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
22
GROUP OF #1 AND #2 CYLINDERS
Are there faults in #1 and #2 cylinders?
Repair or replace faulty parts. NOTE: • Check the fol­lowing items. Spark plugs Fuel injectors Ignition coil Compression ratio • If no abnormal is discovered, check for "IGNI­TION CONTROL SYSTEM" of #1 and #2 cylinders side. <Ref. to EN(DOHC TURBO)-72, IGNI­TION CONTROL SYSTEM, Diag­nostics for Engine Starting Failure.>
Goto DTC P0171 and P0172. <Ref. to EN(DOHC TURBO)-160, DTC P0171 -FUEL TRIM MAL­FUNCTION (A/F TOO LEAN) -, Diagnostic Proce­dure with Diag­nostic Trouble Code (DTC).>
23
GROUP OF #3 AND #4 CYLINDERS
Are there faults in #3 and #4 cylinders?
Repair or replace faulty parts. NOTE: • Check the fol­lowing items. Spark plugs Fuel injectors Ignition coil • If no abnormal is discovered, check for "16. D: IGNITION CON­TROL SYSTEM" of #3 and #4 cyl­inders side. <Ref. to EN(DOHC TURBO)-72, IGNI­TION CONTROL SYSTEM, Diag­nostics for Engine Starting Failure.>
Goto DTC P0171 and P0172. <Ref. to EN(DOHC TURBO)-160, DTC P0171 -FUEL TRIM MAL­FUNCTION (A/F TOO LEAN) -, Diagnostic Proce­dure with Diag­nostic Trouble Code (DTC).>
24
GROUP OF #1 AND #3 CYLINDERS
Are there faults in #1 and #3 cylinders?
Repair or replace faulty parts. NOTE: Check the follow­ing items. • Spark plugs • Fuel injectors • Skipping timing belt teeth
Goto DTC P0171 and P0172. <Ref. to EN(DOHC TURBO)-160, DTC P0171 — FUEL TRIM MAL­FUNCTION (A/F TOO LEAN) —, Diagnostic Proce­dure with Diag­nostic Trouble Code (DTC).>
EN(DOHC TURBO)-179
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
25
GROUP OF #2 AND #4 CYLINDERS
Are there faults in #2 and
Repair or replace
Goto DTC P0171
#4 cylinders?
faulty parts.
and P0172. <Ref.
NOTE:
to EN(DOHC
Check the follow-
TURBO)-160,
ing items.
DTC P0171 —
• Spark plugs
FUEL TRIM MAL-
• Fuel injectors
FUNCTION (A/F
• Compression
TOO LEAN) —,
ratio
Diagnostic Proce-
• Skipping timing
dure with Diag-
belt teeth
nostic Trouble
Code (DTC).>
26
CYLINDER AT RANDOM
Is the engine idle rough?
Goto DTC P0171
Repair or replace
and P0172. <Ref.
faulty parts.
to EN(DOHC
NOTE:
TURBO)-160,
Check the follow-
DTC P0171 —
ing items.
FUEL TRIM MAL-
• Spark plugs
FUNCTION (A/F
• Fuel injectors
TOO LEAN) —,
• Compression
Diagnostic Proce-
ratio
dure with Diag-
nostic Trouble
Code (DTC).>
EN(DOHC TURBO)-180
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics) MEMO:
EN(DOHC TURBO)-181
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
AH: DTC P0327 — KNOCK SENSOR CIRCUIT LOW INPUT —
S088521F94
•  DTC DETECTING CONDITION:
•   Immediately at fault recognition
•  TROUBLE SYMPTOM:
•   Poor driving performance
•   Knocking occurs.
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
for_01_25-35.jpg
EN(DOHC TURBO)-182
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK HARNESS BETWEEN KNOCK
Is the resistance more than
Go to step 2.
Repair harness
SENSOR AND ECM CONNECTOR.
700 ??
and connector.
1) Turn ignition switch to OFF.
NOTE:
2) Disconnect connector from ECM.
In this case,
3) Measure resistance between ECM harness
repair the follow-
connector and chassis ground.
ing:
Connector & terminal
• Open circuit in
(B135) No. 4 — Chassis ground:
harness between
knock sensor and
ECM connector
• Poor contact in
knock sensor con-
nector
• Poor contact in
coupling connec-
tor
2
CHECK KNOCK SENSOR.
Is the resistance more than
Go to step 3.
Repair harness
1) Disconnect connector from knock sensor.
700 ??
and connector.
2) Measure resistance between knock sensor
NOTE:
connector terminal and engine ground.
In this case,
Terminal
repair the follow-
No. 2 Engine ground:
ing:
• Open circuit in
harness between
knock sensor and
ECM connector
• Poor contact in
knock sensor con-
nector
• Poor contact in
coupling connec-
tor
3
CHECK CONDITION OF KNOCK SENSOR
Is the knock sensor instal-
Replace knock
Tighten knock
INSTALLATION.
lation bolt tightened
sensor. <Ref. to
sensor installation
securely?
FU(DOHC
bolt securely.
TURBO)-32,
Knock Sensor.>
EN(DOHC TURBO)-183
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
AI: DTC P0328 — KNOCK SENSOR CIRCUIT HIGH INPUT —
S088521F95
•  DTC DETECTING CONDITION:
•   Immediately at fault recognition
•  TROUBLE SYMPTOM:
•   Poor driving performance
•   Knocking occurs.
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
for_01_25-36.jpg
EN(DOHC TURBO)-184
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK HARNESS BETWEEN KNOCK SENSOR AND ECM CONNECTOR.
Measure resistance of harness between ECM connector and chassis ground. Connector & terminal (B135) No. 4 — Chassis ground:
Is the resistance less than 400 ??
Go to step 2.
Go to step 3.
2
CHECK KNOCK SENSOR.
1) Disconnect connector from knock sensor. 2) Measure resistance between knock sensor connector terminal and engine ground. Terminal No. 2 Engine ground:
Is the resistance less than 400 ??
Replace knock sensor. <Ref. to FU(DOHC TURBO)-32, Knock Sensor.>
Repair ground short circuit in harness between knock sensor con­nector and ECM connector. NOTE: The harness between both connectors is shielded. Repair short circuit of harness together with shield.
3
CHECK INPUT SIGNAL FOR ECM.
1) Connect connectors to ECM and knock sensor. 2) Turn ignition switch to ON. 3) Measure voltage between ECM and chas­sis ground. Connector & terminal (B135) No. 4 (+) Chassis ground (-):
Is the voltage more than 2 V?
Even if MIL lights up, the circuit has returned to a nor­mal condition at this time. (However, the possibility of poor contact still remains.) NOTE: In this case, repair the follow­ing: • Poor contact in knock sensor con­nector • Poor contact in ECM connector • Poor contact in coupling connec­tor
Repair poor con­tact in ECM con­nector.
EN(DOHC TURBO)-185
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
AJ: DTC P0335 — CRANKSHAFT POSITION SENSOR CIRCUIT MALFUNCTION —
  DTC DETECTING CONDITION:
•   Immediately at fault recognition
•  TROUBLE SYMPTOM:
•   Engine stalls.
•   Failure of engine to start
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
for_01_25-37.jpg
EN(DOHC TURBO)-186
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK HARNESS BETWEEN CRANK-
Is the resistance more than
Repair harness
Go to step 2.
SHAFT POSITION SENSOR AND ECM
100 ??
and connector.
CONNECTOR.
NOTE:
1) Turn ignition switch to OFF.
In this case,
2) Disconnect connector from crankshaft posi-
repair the follow-
tion sensor.
ing:
3) Measure resistance of harness between
• Open circuit in
crankshaft position sensor connector and
harness between
engine ground.
crankshaft posi-
Connector & terminal
tion sensor and
(E10) No. 1 Engine ground:
ECM connector
• Poor contact in
ECM connector
• Poor contact in
coupling connec-
tor
2
CHECK HARNESS BETWEEN CRANK-
Is the resistance less than
Repair ground
Go to step 3.
SHAFT POSITION SENSOR AND ECM
10 Q?
short circuit in
CONNECTOR.
harness between
Measure resistance of harness between
crankshaft posi-
crankshaft position sensor connector and
tion sensor and
engine ground.
ECM connector.
Connector & terminal
NOTE:
(E10) No. 1 Engine ground:
The harness
between both
connectors are
shielded. Repair
ground short cir-
cuit in harness
together with
shield.
3
CHECK HARNESS BETWEEN CRANK-
Is the resistance less than
Go to step 4.
Repair harness
SHAFT POSITION SENSOR AND ECM
5Q?
and connector.
CONNECTOR.
NOTE:
Measure resistance of harness between
In this case,
crankshaft position sensor connector and
repair the follow-
engine ground.
ing:
Connector & terminal
• Open circuit in
(E10) No. 2 Engine ground:
harness between
crankshaft posi-
tion sensor and
ECM connector
• Poor contact in
ECM connector
• Poor contact in
coupling connec-
tor
4
CHECK CONDITION OF CRANKSHAFT
Is the crankshaft position
Go to step 5.
Tighten crankshaft
POSITION SENSOR.
sensor installation bolt
position sensor
tightened securely?
installation bolt
securely.
5
CHECK CRANKSHAFT POSITION SENSOR.
Is the resistance between 1
Repair poor con-
Replace crank-
1) Remove crankshaft position sensor.
and 4 kQ?
tact in crankshaft
shaft position sen-
2) Measure resistance between connector
position sensor
sor. <Ref. to
terminals of crankshaft position sensor.
connector.
FU(DOHC
Terminals
TURBO)-30,
No. 1 — No. 2:
Crankshaft Posi-
tion Sensor.>
EN(DOHC TURBO)-187
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
AK: DTC P0336 — CRANKSHAFT POSITION SENSOR CIRCUIT
RANGE/PERFORMANCE PROBLEM —
S088521B43
•  DTC DETECTING CONDITION:
•   Immediately at fault recognition
•  TROUBLE SYMPTOM:
•   Engine stalls.
•   Failure of engine to start
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(DOHC TURBO)-47, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(DOHC TURBO)-44, Inspec­tion Mode.>.
  WIRING DIAGRAM:
for_01_25-38.jpg
EN(DOHC TURBO)-188
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK ANY OTHER DTC ON DISPLAY.
Does the Subaru Select
Inspect DTC
Go to step 2.
Monitor or OBD-II general
P0335 using "List
scan tool indicate DTC
of Diagnostic
P0335?
Trouble Code
(DTC)". <Ref. to
EN(DOHC
TURBO)-82, List
of Diagnostic
Trouble Code
(DTC).>
2
CHECK CONDITION OF CRANKSHAFT
Is the crankshaft position
Go to step 3.
Tighten crankshaft
POSITION SENSOR.
sensor installation bolt
position sensor
Turn ignition switch to OFF.
tightened securely?
installation bolt
securely.
3
CHECK CRANKSHAFT SPROCKET.
Are crankshaft sprocket
Replace crank-
Go to step 4.
Remove front belt cover.
teeth cracked or damaged?
shaft sprocket.
<Ref. to
FU(DOHC
TURBO)-30,
Crankshaft Posi-
tion Sensor.>
4
CHECK INSTALLATION CONDITION OF
Is timing belt dislocated
Repair installation
Replace crank-
TIMING BELT.
from its proper position?
condition of timing
shaft position sen-
Turn crankshaft using ST, and align alignment
belt. <Ref. to
sor. <Ref. to
mark on crankshaft sprocket with alignment
ME(DOHC
FU(DOHC
mark on cylinder block.
TURBO)-48, Tim-
TURBO)-30,
ST 499987500 CRANKSHAFT SOCKET
ing Belt Assem-
Crankshaft Posi-
bly. >
tion Sensor.>
EN(DOHC TURBO)-189
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
AL: DTC P0340 — CAMSHAFT POSITION SENSOR CIRCUIT MALFUNCTION
S088521B44