EN(H6DO)(diag)-135
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CONNECT SUBARU SELECT MONITOR OR
THE GENERAL SCAN TOOL, AND READ
DATA.
1) Turn the ignition switch to OFF.
2) Connect the Subaru Select Monitor or gen-
eral scan tool to data link connector.
3) Turn the ignition switch to ON, and the Sub-
aru Select Monitor power switch to ON.
4) Start the engine.
5) Read the voltage of mass air flow sensor
using Subaru Select Monitor or general scan
tool.
NOTE:•Subaru Select Monitor
For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”.
tor.>
•General scan tool
For detailed operation procedure, refer to the
general scan tool operation manual.
Is the voltage 0.2 — 4.7 V? Even if the mal-
function indicator
light illuminates,
the circuit has
returned to a nor-
mal condition at
this time.
Go to step 2.
2CHECK HARNESS BETWEEN ECM AND
MASS AIR FLOW SENSOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from mass air-
flow sensor.
3) Turn the ignition switch to ON.
4) Measure the voltage between mass air flow
sensor connector and chassis ground.
Connector & terminal
(B3) No. 3 (+) — Chassis ground (–):
Is the voltage more than 5 V? Repair the battery
short circuit of har-
ness between
mass air flow sen-
sor connector and
ECM connector.
Go to step 3.
3CHECK HARNESS BETWEEN ECM AND
MASS AIR FLOW SENSOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM.
3) Measure the resistance of harness
between ECM connector and mass air flow
sensor connector.
Connector & terminal
(B3) No. 2 — (B135) No. 34:
Is the resistance less than 1
Ω?
Replace the mass
air flow sensor.
Mass Air Flow and
Intake Air Temper-
ature Sensor.>
Repair the open
circuit of harness
between mass air
flow sensor con-
nector and ECM
connector.
EN(H6DO)(diag)-137
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK CURRENT DATA.
1) Start the engine.
2) Read the data of intake manifold absolute
pressure signal using Subaru Select Monitor or
general scan tool.
NOTE:
•Subaru Select Monitor
For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”.
tor.>
•General scan tool
For detailed operation procedure, refer to the
general scan tool operation manual.
Is the measured value less
than 13.3 kPa (100 mmHg,
3.94 inHg) ?
Go to step 3.Go to step 2.
2CHECK POOR CONTACT.
Check the poor contact in ECM and manifold
absolute pressure sensor connector.
Is there poor contact in ECM or
manifold absolute pressure
sensor connector?
Repair the poor
contact in ECM or
manifold absolute
pressure sensor
connector.
Even if the mal-
function indicator
light illuminates,
the circuit has
returned to a nor-
mal condition at
this time.
3CHECK OUTPUT SIGNAL OF ECM.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(B134) No. 19 (+) — Chassis ground (–):
Is the voltage more than 4.5 V? Go to step 5.Go to step 4.
4CHECK OUTPUT SIGNAL OF ECM.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(B134) No. 19 (+) — Chassis ground (–):
Does the voltage change by
shaking the ECM harness and
connector?
Repair poor con-
tact in ECM con-
nector.
Replace the ECM.
Engine Control
Module (ECM).>
5CHECK INPUT SIGNAL OF ECM.
Measure the voltage between ECM and chas-
sis ground.
Connector & terminal
(B134) No. 6 (+) — Chassis ground (–):
Is the voltage less than 0.2 V? Go to step 7.Go to step 6.
6CHECK INPUT SIGNAL FOR ECM (USING
SUBARU SELECT MONITOR).
Read the data of atmospheric absolute pres-
sure signal using Subaru Select Monitor.
NOTE:For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”.
tor.>
Is the measured value more
than 13.3 kPa (100 mmHg,
3.94 inHg) when shaking the
ECM harness and connector?
Repair poor con-
tact in ECM con-
nector.
Go to step 7.
7CHECK HARNESS BETWEEN ECM AND
MANIFOLD ABSOLUTE PRESSURE SEN-
SOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from manifold
absolute pressure sensor.
3) Turn the ignition switch to ON.
4) Measure the voltage between manifold
absolute pressure sensor connector and
engine ground.
Connector & terminal
(E28) No. 3 (+) — Engine ground (–):
Is the voltage more than 4.5 V? Go to step 8.Repair the open
circuit of harness
between ECM and
manifold absolute
pressure sensor
connector.
EN(H6DO)(diag)-138
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
8CHECK HARNESS BETWEEN ECM AND
MANIFOLD ABSOLUTE PRESSURE SEN-
SOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM.
3) Measure the resistance of harness
between ECM and manifold absolute pressure
sensor connector.
Connector & terminal
(B134) No. 29 — (E28) No. 1:
Is the resistance less than 1
Ω?
Go to step 9.Repair the open
circuit of harness
between ECM and
manifold absolute
pressure sensor
connector.
9CHECK POOR CONTACT.
Check poor contact of manifold absolute pres-
sure sensor connector.
Is there poor contact in mani-
fold absolute pressure sensor
connector?
Repair the poor
contact of manifold
absolute pressure
sensor connector.
Replace the mani-
fold absolute pres-
sure sensor.
Manifold Absolute
Pressure Sensor.>
Step Check Yes No
EN(H6DO)(diag)-140
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK OUTPUT SIGNAL OF ECM.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(B134) No. 19 (+) — Chassis ground (–):
Is the voltage more than 4.5 V? Go to step 3.Go to step 2.
2CHECK OUTPUT SIGNAL OF ECM.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(B134) No. 19 (+) — Chassis ground (–):
Does the voltage change by
shaking the ECM harness and
connector?
Repair poor con-
tact in ECM con-
nector.
Replace the ECM.
Engine Control
Module (ECM).>
3CHECK INPUT SIGNAL OF ECM.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(B134) No. 6 (+) — Chassis ground (–):
Is the voltage more than 4.5 V? Go to step 5.Go to step 4.
4CHECK INPUT SIGNAL FOR ECM (USING
SUBARU SELECT MONITOR).
Read the data of atmospheric absolute pres-
sure signal using Subaru Select Monitor.
NOTE:For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”.
tor.>
Is the measured value more
than 13.3 kPa (100 mmHg,
3.94 inHg) when shaking the
ECM harness and connector?
Repair poor con-
tact in ECM con-
nector.
Go to step 5.
5CHECK HARNESS BETWEEN ECM AND
MANIFOLD ABSOLUTE PRESSURE SEN-
SOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from manifold
absolute pressure sensor.
3) Turn the ignition switch to ON.
4) Measure the voltage between manifold
absolute pressure sensor connector and
engine ground.
Connector & terminal
(E28) No. 3 (+) — Engine ground (–):
Is the voltage more than 4.5 V? Go to step 6.Repair the open
circuit of harness
between ECM and
manifold absolute
pressure sensor
connector.
6CHECK HARNESS BETWEEN ECM AND
MANIFOLD ABSOLUTE PRESSURE SEN-
SOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM.
3) Measure the resistance of harness
between ECM and manifold absolute pressure
sensor connector.
Connector & terminal
(B134) No. 6 — (E28) No. 2:
Is the resistance less than 1
Ω?
Go to step 7.Repair the open
circuit of harness
between ECM and
manifold absolute
pressure sensor
connector.
7CHECK HARNESS BETWEEN THE MANI-
FOLD ABSOLUTE PRESSURE SENSOR
CONNECTOR.
1) Turn the ignition switch to ON.
2) Measure the voltage between ECM con-
nector and chassis ground.
Connector & terminal
(B134) No. 6 (+) — Chassis ground (–):
Is the voltage more than 4.5 V? Repair the battery
short circuit of har-
ness between
ECM and mani-
fold absolute pres-
sure sensor
connector.
Go to step 8.
EN(H6DO)(diag)-141
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
8CHECK HARNESS BETWEEN ECM AND
MANIFOLD ABSOLUTE PRESSURE SEN-
SOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Measure the resistance of harness
between ECM and manifold absolute pressure
sensor connector.
Connector & terminal
(B134) No. 29 — (E28) No. 1:
Is the resistance less than 1
Ω?
Go to step 9.Repair the open
circuit of harness
between ECM and
manifold absolute
pressure sensor
connector.
9CHECK POOR CONTACT.
Check poor contact of manifold absolute pres-
sure sensor connector.
Is there poor contact in mani-
fold absolute pressure sensor
connector?
Repair the poor
contact of manifold
absolute pressure
sensor connector.
Replace the mani-
fold absolute pres-
sure sensor.
Manifold Absolute
Pressure Sensor.>
Step Check Yes No
EN(H6DO)(diag)-143
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
P0111.
Go to step 2.
2CHECK ENGINE COOLANT TEMPERA-
TURE.
1) Start the engine and warm-up completely.
2) Measure the engine coolant temperature
using the Subaru Select Monitor or general
scan tool.
NOTE:•Subaru Select Monitor
For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”.
tor.>
•General scan tool
For detailed operation procedure, refer to the
general scan tool operation manual.
Is the engine coolant tempera-
ture 75 — 95°C (167 — 203°F)
?
Replace the mass
air flow and intake
air temperature
sensor.
Mass Air Flow and
Intake Air Temper-
ature Sensor.>
Check DTC P0125
using “List of Diag-
nostic Trouble
Code (DTC).”
69, List of Diag-
nostic Trouble
Code (DTC).>
EN(H6DO)(diag)-145
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK CURRENT DATA.
1) Start the engine.
2) Read the data of mass air flow and intake
air temperature sensor signal using Subaru
Select Monitor or general scan tool.
NOTE:
•Subaru Select Monitor
For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”.
tor.>
•General scan tool
For detailed operation procedure, refer to the
general scan tool operation manual.
Is the intake air temperature
above 120°C (248°F) ?
Go to step 2.Repair the poor
contact.
NOTE:
In this case, repair
the following item:
•Poor contact
in mass air flow
and intake air
temperature
sensor
•Poor contact
in ECM
•Poor contact
of coupling con-
nector
•Poor contact
of joint connec-
tor
2CHECK HARNESS BETWEEN MASS AIR
FLOW AND INTAKE AIR TEMPERATURE
SENSOR AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from mass air
flow and intake air temperature sensor.
3) Turn the ignition switch to ON.
4) Read the data of mass air flow and intake
air temperature sensor signal using Subaru
Select Monitor or general scan tool.
NOTE:
•Subaru Select Monitor
For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”.
tor.>
•General scan tool
For detailed operation procedure, refer to the
general scan tool operation manual.
Is the intake air temperature
less than –40°C (–40°F) ?
Replace the mass
air flow and intake
air temperature
sensor.
Mass Air Flow and
Intake Air Temper-
ature Sensor.>
Repair the ground
short circuit of har-
ness between
mass air flow and
intake air tempera-
ture sensor and
ECM connector.
EN(H6DO)(diag)-147
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step Check Yes No
1CHECK CURRENT DATA.
1) Start the engine.
2) Read the data of mass air flow and intake
air temperature sensor signal using Subaru
Select Monitor or general scan tool.
NOTE:
•Subaru Select Monitor
For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”.
tor.>
•General scan tool
For detailed operation procedure, refer to the
general scan tool operation manual.
Is the intake air temperature
less than –40°C (–40°F) ?
Go to step 2.Repair the poor
contact.
NOTE:
In this case, repair
the following item:
•Poor contact
in mass air flow
and intake air
temperature
sensor
•Poor contact
in ECM
•Poor contact
of coupling con-
nector
•Poor contact
of joint connec-
tor
2CHECK HARNESS BETWEEN MASS AIR
FLOW AND INTAKE AIR TEMPERATURE
SENSOR AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from mass air
flow and intake air temperature sensor.
3) Measure the voltage between mass air flow
and intake air temperature sensor connector
and engine ground.
Connector & terminal
(B3) No. 4 (+) — Engine ground (–):
Is the voltage more than 10 V? Repair the battery
short circuit of har-
ness between
mass air flow and
intake air tempera-
ture sensor and
ECM connector.
Go to step 3.
3CHECK HARNESS BETWEEN MASS AIR
FLOW AND INTAKE AIR TEMPERATURE
SENSOR AND ECM CONNECTOR.
1) Turn the ignition switch to ON.
2) Measure the voltage between mass air flow
and intake air temperature sensor connector
and engine ground.
Connector & terminal
(B3) No. 4 (+) — Engine ground (–):
Is the voltage more than 10 V? Repair the battery
short circuit of har-
ness between
mass air flow and
intake air tempera-
ture sensor and
ECM connector.
Go to step 4.