EN(H6DO)(diag)-244
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
BS:DTC P0306 CYLINDER 6 MISFIRE DETECTED
DTC DETECTING CONDITION:
•Detected when two consecutive driving cycles with fault occur.
•Immediately at fault recognition(A misfire which could damage catalyst occurs.)
•GENERAL DESCRIPTION
TROUBLE SYMPTOM:
•Engine stalls.
•Erroneous idling
•Rough driving
CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode
WIRING DIAGRAM:
EN-03654
E6E17
E5E16
E43E44
12121212
109811
4248434445
ECMB137
E5E16E6E17
B21
E2
FUEL INJECTORNO. 1FUEL INJECTORNO. 2FUEL INJECTORNO. 3FUEL INJECTORNO. 4
BATTERY
1212
1213
4647
E43E44
FUEL INJECTORNO. 5FUEL INJECTORNO. 6
SBF-7
B47
MAIN RELAY
12
35
46
B47
3412
56
12
B21
123412131415567816171819910 1120212223 24 25 2627 28 29 3031 32 33
3534 37363938 41404342 4445 47464948 51505352 54
E
B137
85610 11 12 13 14 157213416
3019 20 2228 29
91718 2521 23 243126 27
EN(H6DO)(diag)-245
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK ANY OTHER DTC ON DISPLAY.Is any other DTC displayed? Check DTC using
“List of Diagnostic
Tr o u b l e C o d e
(DTC)”.
69, List of Diag-
nostic Trouble
Code (DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0301, P0302,
P303, P0304,
P0305 and P0306.
Go to step 2.
2CHECK OUTPUT SIGNAL OF ECM.
1) Turn the ignition switch to ON.
2) Measure the voltage between ECM con-
nector and chassis ground on faulty cylinders.
Connector & terminal
#1 (B137) No. 8 (+) — Chassis ground (–):
#2 (B137) No. 9 (+) — Chassis ground (–):
#3 (B137) No. 10 (+) — Chassis ground (–):
#4 (B137) No. 11 (+) — Chassis ground (–):
#5 (B137) No. 12 (+) — Chassis ground (–):
#6 (B137) No. 13 (+) — Chassis ground (–):
Is the voltage more than 10 V? Go to step 7.Go to step 3.
3CHECK HARNESS BETWEEN FUEL INJEC-
TOR AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from fuel injector
on faulty cylinders.
3) Measure the resistance between ECM con-
nector 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:
#5 (E43) No. 1 — Engine ground:
#6 (E44) No. 1 — Engine ground:
Is the resistance more than 1
MΩ?
Go to step 4.Repair the ground
short circuit of har-
ness between fuel
injector and ECM
connector.
4CHECK HARNESS BETWEEN FUEL INJEC-
TOR AND ECM CONNECTOR.
Measure the resistance of harness connector
between ECM connector and fuel injector on
faulty cylinders.
Connector & terminal
#1 (B137) No. 8 — (E5) No. 1:
#2 (B137) No. 9 — (E16) No. 1:
#3 (B137) No. 10 — (E6) No. 1:
#4 (B137) No. 11 — (E17) No. 1:
#5 (B137) No. 12 — (E43) No. 1:
#6 (B137) No. 13 — (E44) No. 1:
Is the resistance less than 1
Ω?
Go to step 5.Repair the har-
ness and connec-
tor.
NOTE:In this case, repair
the following item:
•Open circuit
of harness be-
tween ECM and
fuel injector
connector
•Poor contact
of coupling con-
nector
5CHECK FUEL INJECTOR.
Measure the resistance between fuel injector
terminals on faulty cylinder.
Te r m i n a l s
No. 1 — No. 2:
Is the resistance between 5 —
20 Ω?
Go to step 6.Replace the faulty
fuel injector.
Fuel Injector.>
EN(H6DO)(diag)-246
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
6CHECK POWER SUPPLY LINE.
1) Turn the ignition switch to ON.
2) Measure the voltage between fuel injector
and engine ground on faulty cylinders.
Connector & terminal
#1 (E5) No. 2 (+) — Engine ground (–):
#2 (E16) No. 2 (+) — Engine ground (–):
#3 (E6) No. 2 (+) — Engine ground (–):
#4 (E17) No. 2 (+) — Engine ground (–):
#5 (E43) No. 2 (+) — Engine ground (–):
#6 (E44) No. 2 (+) — Engine ground (–):
Is the voltage more than 10 V? Repair the poor
contact of all con-
nectors in fuel
injector circuit.
Repair the har-
ness and connec-
tor.
NOTE:In this case, repair
the following item:
•Open circuit
of harness be-
tween main re-
lay and fuel
injector on
faulty cylinders
•Poor contact
of coupling con-
nector
•Poor contact
of main relay
connector
•Poor contact
of fuel injector
connector on
faulty cylinders
7CHECK HARNESS BETWEEN FUEL INJEC-
TOR AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from fuel injector
on faulty cylinders.
3) Turn the ignition switch to ON.
4) Measure the voltage between ECM con-
nector and chassis ground on faulty cylinders.
Connector & terminal
#1 (B137) No. 8 (+) — Chassis ground (–):
#2 (B137) No. 9 (+) — Chassis ground (–):
#3 (B137) No. 10 (+) — Chassis ground (–):
#4 (B137) No. 11 (+) — Chassis ground (–):
#5 (B137) No. 12 (+) — Chassis ground (–):
#6 (B137) No. 13 (+) — Chassis ground (–):
Is the voltage more than 10 V? Repair the battery
short circuit of har-
ness between
ECM and fuel
injector. After
repair, replace the
ECM.
Engine Control
Module (ECM).>
Go to step 8.
8CHECK FUEL INJECTOR.
1) Turn the ignition switch to OFF.
2) Measure the resistance between fuel injec-
tor terminals on faulty cylinder.
Te r m i n a l s
No. 1 — No. 2:
Is the resistance less than 1
Ω?
Replace the faulty
fuel injector
Fuel Injector.> and
ECM.
Engine Control
Module (ECM).>
Go to step 9.
9CHECK INSTALLATION OF CAMSHAFT PO-
SITION SENSOR/CRANKSHAFT POSITION
SENSOR.
Is the camshaft position sensor
or crankshaft position sensor
loosely installed?
Tighten the cam-
shaft position sen-
sor or crankshaft
position sensor.
Go to step 10.
10 CHECK CRANK PLATE.Is the crank sprocket rusted or
the teeth of crank plate bro-
ken?
Replace the crank
plate.
Cylinder Block.>
Go to step 11.
11 CHECK INSTALLATION CONDITION OF
TIMING CHAIN.
Tu r n t h e c r a n k s h a f t u s i n g S T, a n d a l i g n a l i g n -
ment mark on crank sprocket with alignment
mark on cylinder block.
ST 18252AA000 CRANKSHAFT
SOCKET
Is the timing chain dislocated
from its proper position?
Correct the instal-
lation condition of
timing chain.
Timing Chain
Assembly.>
Go to step 12.
Step Check Yes No
EN(H6DO)(diag)-247
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
12 CHECK FUEL LEVEL.Is the fuel meter indication
lower than the “Lower” level?
Replenish fuel so
that fuel meter
indication is higher
than the “Lower”
level. After replen-
ishing fuel, Go to
step 13.
Go to step 13.
13 CHECK STATUS OF MALFUNCTION INDI-
CATOR LIGHT.
1) Clear the memory using the Subaru Select
Monitor or the general scan tool.
NOTE:•Subaru Select Monitor
•General scan tool
Refer to operating manuals for the general
scan tool.
2) Start the engine, and drive the vehicle more
than 10 minutes.
Does the malfunction indicator
light illuminate or blink?
Go to step 15.Go to step 14.
14 CHECK CAUSE OF MISFIRE.Has the cause of misfire been
detected while running the
engine?
Finish diagnostics
operation, if the
engine has no
abnormality.
Repair the poor
contact.
NOTE:In this case, repair
the following item:
•Poor contact
of ignition coil
connector
•Poor contact
of fuel injector
connector on
faulty cylinders
•Poor contact
in ECM connec-
tor
•Poor contact
of coupling con-
nector
15 CHECK AIR INTAKE SYSTEM.Is there any fault in air intake
system?
Repair the air
intake system.
NOTE:
Check the follow-
ing item.
•Are there air
leaks or air suc-
tion caused by
loose or dislo-
cated nuts and
bolts?
•Are there
cracks or any
disconnection
of hoses?
Go to step 16.
16 CHECK MISFIRE SYMPTOM.
1) Turn the ignition switch to ON.
2) Read DTC.
Does the Subaru Select Moni-
tor or general scan tool indi-
cate only one DTC?
Go to step 22.Go to step 17.
17 CHECK ANY OTHER DTC ON DISPLAY.Are DTC P0301 and P0302
displayed?
Go to step 23.Go to step 18.
Step Check Yes No
EN(H6DO)(diag)-248
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
18 CHECK DTC ON DISPLAY.Are DTC P0303 and P0304
displayed?
Go to step 24.Go to step 19.
19 CHECK DTC ON DISPLAY.Are DTC P0305 and P0306
displayed?
Go to step 25.Go to step 20.
20 CHECK DTC ON DISPLAY.Are DTC P0301, P0303 and
P0305 displayed?
Go to step 26.Go to step 21.
21 CHECK DTC ON DISPLAY.Are DTC P0302, P0304 and
P0306 displayed?
Go to step 27.Go to step 28.
22 ONLY ONE CYLINDERIs there any fault in the cylin-
der?
Repair or replace
faulty par ts.
NOTE:Check the follow-
ing item.
•Spark plug
•Fuel injector
•Compression
ratio
Check DTC
P0171, P0172,
P0174 or P0175
using “List of Diag-
nostic Trouble
Code (DTC)”.
69, List of Diag-
nostic Trouble
Code (DTC).>
23 GROUP OF #1 AND #2 CYLINDERSAre there any faults in #1 and
#2 cylinders?
Repair or replace
faulty par ts.
NOTE:•Check the fol-
lowing item.
•Spark plug
•Fuel injec-
tor
•Ignition
coil
•Compres-
sion ratio
•If any fault
are not found,
check the “IG-
NITION CON-
TROL
SYSTEM” of #1
and #2 cylin-
ders side.
EN(H6DO)(di-
ag)-63, IGNI-
TION
CONTROL
SYSTEM, Diag-
nostics for En-
gine Starting
Failure.>
Check DTC
P0171, P0172,
P0174 or P0175
using “List of Diag-
nostic Trouble
Code (DTC)”.
69, List of Diag-
nostic Trouble
Code (DTC).>
Step Check Yes No
EN(H6DO)(diag)-249
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
24 GROUP OF #3 AND #4 CYLINDERSAre there any faults in #3 and
#4 cylinders?
Repair or replace
faulty par ts.
NOTE:
•Check the fol-
lowing item.
•Spark plug
•Fuel injec-
tor
•Ignition
coil
•If any fault
are not found,
check the “IG-
NITION CON-
TROL
SYSTEM” of #3
and #4 cylin-
ders side.
EN(H6DO)(di-
ag)-63, IGNI-
TION
CONTROL
SYSTEM, Diag-
nostics for En-
gine Starting
Failure.>
Check DTC
P0171, P0172,
P0174 or P0175
using “List of Diag-
nostic Trouble
Code (DTC)”.
69, List of Diag-
nostic Trouble
Code (DTC).>
25 GROUP OF #5 AND #6 CYLINDERSAre there any faults in #5 and
#6 cylinders?
Repair or replace
faulty par ts.
NOTE:•Check the fol-
lowing item.
•Spark plug
•Fuel injec-
tor
•Ignition
coil
•Compres-
sion ratio
•If any fault
are not found,
check the “IG-
NITION CON-
TROL
SYSTEM” of #5
and #6 cylin-
ders side.
EN(H6DO)(di-
ag)-63, IGNI-
TION
CONTROL
SYSTEM, Diag-
nostics for En-
gine Starting
Failure.>
Check DTC
P0171, P0172,
P0174 or P0175
using “List of Diag-
nostic Trouble
Code (DTC)”.
69, List of Diag-
nostic Trouble
Code (DTC).>
Step Check Yes No
EN(H6DO)(diag)-250
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
26 GROUP OF #1, #3 AND #5 CYLINDERS.Is there any fault in #1, #3 and
#5 cylinders?
Repair or replace
faulty par ts.
NOTE:
Check the follow-
ing item.
•Spark plug
•Fuel injector
•Skipping tim-
ing chain teeth
Check DTC
P0171, P0172,
P0174 or P0175
using “List of Diag-
nostic Trouble
Code (DTC)”.
69, List of Diag-
nostic Trouble
Code (DTC).>
27 GROUP OF #2, #4 AND #6 CYLINDERS.Is there any fault in #2, #4 and
#6 cylinders?
Repair or replace
faulty par ts.
NOTE:Check the follow-
ing item.
•Spark plug
•Fuel injector
•Compression
ratio
•Skipping tim-
ing chain teeth
Check DTC
P0171, P0172,
P0174 or P0175
using “List of Diag-
nostic Trouble
Code (DTC)”.
69, List of Diag-
nostic Trouble
Code (DTC).>
28 CYLINDER AT RANDOMIs the engine idle rough? Check DTC
P0171, P0172,
P0174 or P0175
using “List of Diag-
nostic Trouble
Code (DTC)”.
69, List of Diag-
nostic Trouble
Code (DTC).>
Repair or replace
faulty par ts.
NOTE:Check the follow-
ing item.
•Spark plug
•Fuel injector
•Compression
ratio
Step Check Yes No
EN(H6DO)(diag)-270
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
CC:DTC P0442 EVAPORATIVE EMISSION CONTROL SYSTEM LEAK DETECT-
ED (SMALL LEAK)
DTC DETECTING CONDITION:
•Detected when two consecutive driving cycles with fault occur.
•GENERAL DESCRIPTION
TROUBLE SYMPTOM:
•Fuel odor
•There is a hole of more than 1.0 mm (0.04 in) dia. in evaporation system or fuel tank.
CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode
Step Check Yes No
1CHECK ANY OTHER DTC ON DISPLAY.Is any other DTC displayed? Check the appro-
priate DTC using
the “List of Diag-
nostic Trouble
Code (DTC)”.
69, List of Diag-
nostic Trouble
Code (DTC).>
Go to step 2.
2CHECK FUEL FILLER CAP.
1) Turn the ignition switch to OFF.
2) Check the fuel filler cap.
NOTE:
The DTC is stored in memory if fuel filler cap is
or was loose or if the cap chain has caught
while tightening.
Is the fuel filler cap tightened
securely?
Go to step 3.Tighten fuel filler
cap securely.
3CHECK FUEL FILLER CAP.Is the fuel filler cap SUBARU
genuine?
Go to step 4.Replace with a
SUBARU genuine
fuel filler cap.
4CHECK FUEL FILLER PIPE PACKING.Is there any damage to the
seal between fuel filler cap and
fuel filler pipe?
Repair or replace
the fuel filler cap
and fuel filler pipe.
Fuel Filler Pipe.>
Go to step 5.
5CHECK DRAIN VALVE.
1) Connect the test mode connector.
2) Turn the ignition switch to ON.
3) Operate the drain valve.
NOTE:
Drain valve operation can also be executed us-
ing Subaru Select Monitor. Refer to “Compulso-
ry Valve Operation Check Mode” for
procedures.
Does the drain valve operate? Go to step 6.Replace the drain
valve.
Drain Valve.>