EN(H6DO)(diag)-264
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 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 POWER SUPPLY OF CAMSHAFT
POSITION SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from camshaft
position sensor.
3) Measure the voltage between camshaft
position sensor connector and engine ground.
Connector & terminal
(E73) No. 1 (+) — Engine ground (–):
Is the voltage more than 10 V? Repair the battery
short circuit
between main
relay connector
and camshaft
position sensor
connector.
Go to step 3.
3CHECK POWER SUPPLY OF CAMSHAFT
POSITION SENSOR.
1) Turn the ignition switch to ON.
2) Measure the voltage between camshaft
position sensor connector and engine ground.
Connector & terminal
(E73) No. 1 (+) — Engine ground (–):
Is the voltage more than 10 V? Go to step 4.Repair the open or
ground short cir-
cuit between main
relay connector
and camshaft
position sensor
connector.
4CHECK HARNESS BETWEEN CAMSHAFT
POSITION SENSOR CONNECTOR AND
ECM.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the resistance between camshaft
position sensor connector and ECM.
Connector & terminal
(E73) No. 2 — (B134) No. 11:
(E73) No. 3 — (B134) No. 22:
Is the resistance less than 1
Ω?
Go to step 5.Repair the open
circuit between
camshaft position
sensor and ECM.
5CHECK HARNESS BETWEEN CAMSHAFT
POSITION SENSOR CONNECTOR AND
ECM.
Measure the resistance between camshaft
position sensor connector and engine ground.
Connector & terminal
(E73) No. 2 — Engine ground:
Is the resistance more than 1
MΩ?
Go to step 6.Repair the ground
short circuit
between camshaft
position sensor
and ECM.
6CHECK CONDITION OF CAMSHAFT POSI-
TION SENSOR.
Is the camshaft position sensor
installation bolt tightened
securely?
Go to step 7.Tighten the cam-
shaft position sen-
sor installation bolt
securely.
7CHECK CAMSHAFT POSITION SENSOR.
Check waveform of camshaft position sensor.
Is there any abnormality in
waveform?
Replace the cam-
shaft position sen-
sor.
Crankshaft Posi-
tion Sensor.>
Go to step 8.
8CHECK POOR CONTACT.
Check poor contact of ECM connector.
Is there poor contact in ECM
connector?
Repair poor con-
tact in ECM con-
nector.
Replace the ECM.
Engine Control
Module (ECM).>
EN(H6DO)(diag)-266
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 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 POWER SUPPLY OF CAMSHAFT
POSITION SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from camshaft
position sensor.
3) Measure the voltage between camshaft
position sensor connector and engine ground.
Connector & terminal
(E74) No. 1 (+) — Engine ground (–):
Is the voltage more than 10 V? Repair the battery
short circuit
between main
relay connector
and camshaft
position sensor
connector.
Go to step 3.
3CHECK POWER SUPPLY OF CAMSHAFT
POSITION SENSOR.
1) Turn the ignition switch to ON.
2) Measure the voltage between camshaft
position sensor connector and engine ground.
Connector & terminal
(E74) No. 1 (+) — Engine ground (–):
Is the voltage more than 10 V? Go to step 4.Repair the open or
ground short cir-
cuit between main
relay connector
and camshaft
position sensor
connector.
4CHECK HARNESS BETWEEN CAMSHAFT
POSITION SENSOR CONNECTOR AND
ECM.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the resistance between camshaft
position sensor connector and ECM.
Connector & terminal
(E74) No. 2 — (B134) No. 21:
(E74) No. 3 — (B134) No. 22:
Is the resistance less than 1
Ω?
Go to step 5.Repair the open
circuit between
camshaft position
sensor and ECM.
5CHECK HARNESS BETWEEN CAMSHAFT
POSITION SENSOR CONNECTOR AND
ECM.
Measure the resistance between camshaft
position sensor connector and engine ground.
Connector & terminal
(E74) No. 2 — Engine ground:
Is the resistance more than 1
MΩ?
Go to step 6.Repair the ground
short circuit
between camshaft
position sensor
and ECM.
6CHECK CONDITION OF CAMSHAFT POSI-
TION SENSOR.
Is the camshaft position sensor
installation bolt tightened
securely?
Go to step 7.Tighten the cam-
shaft position sen-
sor installation bolt
securely.
7CHECK CAMSHAFT POSITION SENSOR.
Check waveform of camshaft position sensor.
Is there any abnormality in
waveform?
Replace the cam-
shaft position sen-
sor.
Camshaft Position
Sensor.>
Go to step 8.
8CHECK POOR CONTACT.
Check poor contact of ECM connector.
Is there poor contact in ECM
connector?
Repair poor con-
tact in ECM con-
nector.
Replace the ECM.
Engine Control
Module (ECM).>
EN(H6DO)(diag)-269
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 the appro-
priate DTC using
the “List of Diag-
nostic Trouble
Code (DTC)”.
69, List of Diag-
nostic Trouble
Code (DTC).>
NOTE:In this case, it is
not necessary to
inspect DTC
P0420.
Go to step 2.
2CHECK HARNESS BETWEEN ECM AND
REAR OXYGEN SENSOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and
rear oxygen sensor.
3) Measure the resistance of harness
between ECM and rear oxygen sensor con-
nector.
Connector & terminal
(B134) No. 4 — (E61) No. 3:
(B134) No. 30 — (E61) No. 4:
(B134) No. 15 — (E25) No. 3:
(B134) No. 30 — (E25) No. 4:
Is the resistance less than 1
Ω?
Go to step 3.Repair the open
circuit of harness
between ECM and
rear oxygen sen-
sor connector.
3CHECK HARNESS BETWEEN ECM AND
REAR OXYGEN SENSOR CONNECTOR.
Measure the resistance between rear oxygen
sensor harness connector and chassis ground.
Connector & terminal
(B135) No. 1 — Chassis ground:
Is the resistance less than 1
Ω?
Go to step 4.Repair the open
circuit between
ECM and rear oxy-
gen sensor con-
nector.
4 CHECK EXHAUST SYSTEM.
Check for gas leaks or air suction caused by
loose or dislocated nuts and bolts, and open
hole at exhaust pipes.
NOTE:Check the following positions.
•Between cylinder head and front exhaust
pipe
•Between front exhaust pipe and front catalyt-
ic converter
•Between front catalytic converter and rear
catalytic converter
Is there any fault in exhaust
system?
Repair or replace
the exhaust sys-
tem.
General Descrip-
tion.>
Go to step 5.
5CHECK CATALYTIC CONVERTER.Is there damage on rear face
or front face of catalytic con-
ver ter?
Replace the cata-
lytic converter.
Front Catalytic
Converter.>
Contact the SOA
service center.
EN(H6DO)(diag)-273
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK OUTPUT SIGNAL OF ECM.
1) Turn the ignition switch to ON.
2) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B136) No. 17 (+) — Chassis ground (–):
Is the voltage more than 10 V? Go to step 2.Go to step 3.
2CHECK POOR CONTACT.
Check poor contact of ECM connector.
Is there poor contact in ECM
connector?
Repair poor con-
tact in ECM con-
nector.
Even if the mal-
function indicator
light illuminates,
the circuit has
returned to a nor-
mal condition at
this time. (How-
ever, the possibility
of poor contact still
remains.)
NOTE:In this case, repair
the following item:
•Poor contact
in drain valve
connector
•Poor contact
in ECM connec-
tor
•Poor contact
of coupling con-
nector
3CHECK HARNESS BETWEEN DRAIN
VALVE AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from drain valve
and ECM.
3) Measure the resistance of harness
between drain valve connector and chassis
ground.
Connector & terminal
(R143) No. 2 — Chassis ground:
Is the resistance more than 1
MΩ?
Go to step 4.Repair ground
short circuit of har-
ness between
ECM and drain
valve connector.
4CHECK HARNESS BETWEEN DRAIN
VALVE AND ECM CONNECTOR.
Measure the resistance of harness between
ECM and drain valve connector.
Connector & terminal
(B136) No. 17 — (R143) No. 2:
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
drain valve con-
nector
•Poor contact
of coupling con-
nector
5CHECK DRAIN VALVE.
Measure the resistance between drain valve
terminals.
Te r m i n a l s
No. 1 — No. 2:
Is the resistance between 10
— 100 Ω?
Go to step 6.Replace the drain
valve.
Drain Valve.>
EN(H6DO)(diag)-274
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
6CHECK POWER SUPPLY TO DRAIN VALVE.
1) Turn the ignition switch to ON.
2) Measure the voltage between drain valve
and chassis ground.
Connector & terminal
(R143) No. 1 (+) — Chassis ground (–):
Is the voltage more than 10 V? Go to step 7.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 drain
valve
•Poor contact
of coupling con-
nector
•Poor contact
of main relay
connector
7CHECK POOR CONTACT.
Check poor contact in drain valve connector.
Is there poor contact in drain
valve connector?
Repair poor con-
tact in drain valve
connector.
Contact with SOA
Service Center.
Step Check Yes No
EN(H6DO)(diag)-276
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK INPUT SIGNAL OF ECM.
1) Turn the ignition switch to OFF.
2) Connect the test mode connector at the
lower portion of instrument panel (on the
driver’s side).
3) Turn the ignition switch to ON.
4) While operating the drain valve, measure
voltage between ECM and chassis ground.
NOTE:
Drain valve operation can also be executed us-
ing Subaru Select Monitor. Refer to “Compulso-
ry Valve Operation Check Mode” for
procedures.
Connector & terminal
(B136) No. 17 (+) — Chassis ground (–):
Is the voltage 0 — 10 V? Go to step 2.Even if the mal-
function indicator
light illuminates,
the circuit has
returned to a nor-
mal condition at
this time. In this
case, repair the
poor contact in
ECM connector.
2CHECK INPUT SIGNAL OF ECM.
1) Turn the ignition switch to ON.
2) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B136) No. 17 (+) — Chassis ground (–):
Is the voltage more than 10 V? Go to step 4.Go to step 3.
3CHECK POOR CONTACT.
Check poor contact of ECM connector.
Is there poor contact in ECM
connector?
Repair poor con-
tact in ECM con-
nector.
Replace the ECM.
Engine Control
Module (ECM).>
4CHECK HARNESS BETWEEN DRAIN
VALVE AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from the drain
valve.
3) Turn the ignition switch to ON.
4) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B136) No. 17 (+) — Chassis ground (–):
Is the voltage more than 10 V? Repair battery
short circuit of har-
ness between
ECM and drain
valve connector.
After repair,
replace the ECM.
Engine Control
Module (ECM).>
Go to step 5.
5CHECK DRAIN VALVE.
1) Turn the ignition switch to OFF.
2) Measure the resistance between drain
valve terminals.
Te r m i n a l s
No. 1 — No. 2:
Is the resistance less than 1
Ω?
Replace the drain
valve
Drain Valve.> and
ECM
Engine Control
Module (ECM).>.
Go to step 6.
6CHECK POOR CONTACT.
Check poor contact of ECM connector.
Is there poor contact in ECM
connector?
Repair poor con-
tact in ECM con-
nector.
Replace the ECM.
Engine Control
Module (ECM).>
EN(H6DO)(diag)-280
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK CURRENT DATA.
1) Turn the ignition switch to OFF.
2) Remove the fuel filler cap.
3) Install the fuel filler cap.
4) Turn the ignition switch to ON.
5) Read the data of fuel tank pressure sensor
signal using Subaru Select Monitor.
NOTE:•Subaru Select Monitor
For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”.
tor.>
Is the measured value less
than –2.8 kPa (–21.0 mmHg, –
0.827 inHg)?
Go to step 2.Even if the mal-
function indicator
light illuminates,
the circuit has
returned to a nor-
mal condition at
this time.
2CHECK POWER SUPPLY TO FUEL TANK
PRESSURE SENSOR.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(B135) No. 22 (+) — Chassis ground (–):
Is the voltage more than 4.5 V? Go to step 4.Go to step 3.
3CHECK POWER SUPPLY TO FUEL TANK
PRESSURE SENSOR.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(B135) No. 22 (+) — Chassis ground (–):
Does the voltage change by
shaking the ECM harness and
connector?
Repair poor con-
tact in ECM con-
nector.
Contact with SOA
Service Center.
4CHECK INPUT SIGNAL OF ECM.
Measure the voltage between ECM and chas-
sis ground.
Connector & terminal
(B135) No. 32 (+) — Chassis ground (–):
Is the voltage less than 0.2 V? Go to step 6.Go to step 5.
5CHECK INPUT SIGNAL FOR ECM (USING
SUBARU SELECT MONITOR).
Read the data of fuel tank pressure sensor sig-
nal using Subaru Select Monitor.
NOTE:
•Subaru Select Monitor
For detailed operation procedure, refer to
“READ CURRENT DATA FOR ENGINE”.
tor.>
Does the measured value
change by shaking ECM har-
ness and connector?
Repair poor con-
tact in ECM con-
nector.
Go to step 6.
6CHECK HARNESS BETWEEN ECM AND
COUPLING CONNECTOR IN REAR WIRING
HARNESS.
1) Turn the ignition switch to OFF.
2) Remove the rear seat cushion.
3) Separate rear wiring harness and fuel tank
cord.
4) Turn the ignition switch to ON.
5) Measure the voltage between rear wiring
harness connector and chassis ground.
Connector & terminal
(R15) No. 11 (+) — Chassis ground (–):
Is the voltage more than 4.5 V? Go to step 7.Repair the har-
ness and connec-
tor.
NOTE:In this case, repair
the following item:
•Open circuit
of harness be-
tween ECM and
rear wiring har-
ness connector
•Poor contact
of coupling con-
nector
EN(H6DO)(diag)-281
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
7CHECK HARNESS BETWEEN ECM AND
COUPLING CONNECTOR IN REAR WIRING
HARNESS.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM.
3) Measure the resistance of harness
between ECM and rear wiring harness con-
nector.
Connector & terminal
(B135) No. 30 — (R15) No. 2:
Is the resistance less than 1
Ω?
Go to step 8.Repair the har-
ness and connec-
tor.
NOTE:In this case, repair
the following item:
•Open circuit
of harness be-
tween ECM and
rear wiring har-
ness connector
•Poor contact
of coupling con-
nector
•Poor contact
of joint connec-
tor
8CHECK HARNESS BETWEEN ECM AND
COUPLING CONNECTOR IN REAR WIRING
HARNESS.
Measure the resistance of harness between
rear wiring harness connector and chassis
ground.
Connector & terminal
(R15) No. 2 — Chassis ground:
Is the resistance more than 1
MΩ?
Go to step 9.Repair short circuit
to ground in har-
ness between
ECM and rear wir-
ing harness con-
nector.
9CHECK FUEL TANK CORD.
1) Disconnect the connector from fuel tank
pressure sensor.
2) Measure the resistance of fuel tank cord.
Connector & terminal
(R60) No. 11 — (R47) No. 3:
Is the resistance less than 1
Ω?
Go to step 10.Repair open circuit
in fuel tank cord.
10 CHECK FUEL TANK CORD.
Measure the resistance of fuel tank cord.
Connector & terminal
(R60) No. 2 — (R47) No. 1:
Is the resistance less than 1
Ω?
Go to step 11.Repair open circuit
in fuel tank cord.
11 CHECK FUEL TANK CORD.
Measure the resistance of harness between
fuel tank pressure sensor connector and
engine ground.
Connector & terminal
(R47) No. 2 — Chassis ground:
Is the resistance more than 1
MΩ?
Go to step 12.Repair ground
short circuit in fuel
tank cord.
12 CHECK POOR CONTACT.
Check poor contact in fuel tank pressure sen-
sor connector.
Is there poor contact in fuel
tank pressure sensor connec-
tor?
Repair poor con-
tact in fuel tank
pressure sensor
connector.
Replace the fuel
tank pressure sen-
sor.
Fuel Tank Pres-
sure Sensor.>
Step Check Yes No