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OBD0145A
1CONNECT SUBARU SELECT MONITOR OR
THE OBD-II GENERAL SCAN TOOL, AND
READ DATA.
1) Turn ignition switch to OFF.
2) Connect Subaru Select Monitor or the OBD-II general
scan tool to data link connector.
3) Turn ignition switch to ON and Subaru Select Monitor or
OBD-II general scan tool switch to ON.
4) Start engine.
OBD0185
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.
Subaru Select Monitor
Designate mode using function key.
Function mode: F10
F10: Throttle position sensor output signal is indicated.
: Is the voltage less than 0.1 V?
: Go to step 2.
: Go to next.
: Is the voltage more than 4.9 V?
: Go to step 4.
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. A temporary poor
contact of the connector may be the cause. Check
and repair the following connectors.
Throttle position sensor connector.
ECM connector
Coupling connector (B21)
OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
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OBD0698A
2CHECK INPUT SIGNAL FOR ECM. (USING
VOLTAGE METER AND SUBARU SELECT
MONITOR.)
1) Measure voltage between ECM and body while throttle
valve is fully closed.
: Connector & terminal
(B84) No. 22—Body/4.5 V, or more
: Go to next step.
: Go to next.
: Is the voltage more than 4.5 V while shaking
harness and connector of ECM?
: Repair poor contact in ECM connector.
: Replace ECM.
OBD0699A
2) Measure signal voltage between ECM and body.
: Connector & terminal
(B84) No. 24—Body/0.1 V, or less
: Go to next.
: Go to step 3.
: Is the voltage more than 0.1 V while shaking
harness and connector of ECM and monitor-
ing the value with Subaru select monitor?
: Repair poor contact in ECM connector.
: Go to step 3.
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OBD0700A
3CHECK HARNESS CONNECTOR BETWEEN
ECM AND THROTTLE POSITION SENSOR.
1) Turn ignition switch to OFF.
2) Disconnect connectors from throttle position sensor.
3) Turn ignition switch to ON.
4) Measure voltage between throttle position sensor con-
nector and body.
: Connector & terminal
(E13) No. 3—Body/4.5 V, or more
: Repair harness and connector.
NOTE:
In this case, the possible causes are:
1Open circuit of the harness between connector (E13)
terminal No. 3 and connector (B84) terminal No. 22, or
the following:
2Poor contact in throttle position sensor connector
3Poor contact in ECM connector
4Poor contact in coupling connector (B21)
: Go to the next step.
OBD0701A
5) Turn ignition switch to OFF.
6) Measure resistance of harness between ECM connec-
tor and throttle position sensor connector.
: Connector & terminal
(B84) No. 24—(E13) No. 2/10Ω, or less
: Repair harness and connector.
NOTE:
In this case, the following are the possible causes.
1Open circuit between connector (B84) terminal No. 24
and connector (E13) terminal No. 2.
2Poor contact in ECM connector.
3Poor contact in throttle position sensor connector
4Poor contact in coupling connector (B21)
: Go to next step.
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OBD0702A
7) Measure resistance of harness between throttle posi-
tion sensor connector and body.
: Connector & terminal
(E13) No. 2—Body/10Ω, or less
: Repair short circuit of harness between throttle
position sensor and ECM connector.
: Go to next.
: Is there poor contact in throttle position
sensor connector?
: Repair poor contact in throttle position sensor
connector.
: Replace throttle position sensor.
OBD0703A
4CHECK HARNESS CONNECTOR BETWEEN
THROTTLE POSITION SENSOR AND BODY.
1) Turn ignition switch to OFF.
2) Disconnect connector from throttle position sensor.
3) Measure resistance of harness between throttle posi-
tion sensor connector and body.
: Connector & terminal
(E13) No. 1—Body/10Ω, or less
: Repair open circuit of harness between throttle
position sensor and ECM connector.
: Go to the next step.
OBD0704A
4) Turn ignition switch to ON.
5) Measure voltage between throttle position sensor con-
nector and body.
: Connector & terminal
(E13) No. 2—Body/4.9 V, or more
: Repair short circuit of harness between throttle
position sensor and ECM connector.
: Replace throttle position sensor.
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OBD0189
H: DTC P0121
—THROTTLE POSITION SENSOR CIRCUIT
RANGE/PERFORMANCE PROBLEM (TH
—R)
—
DESCRIPTION:
Refer to“G: DTC P0120—THROTTLE POSITION SEN-
SOR CIRCUIT MALFUNCTION—[T11G0]”.
DTC DETECTING CONDITION:
Two consecutive trips with fault
TROUBLE SYMPTOM:
Erroneous idling
Engine stalls.
Poor driving performance
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Check DTC P0120 on display.
No
Ye s
Inspect DTC P0120 using“11. Diagnostics Chart
with Trouble Code [T1100]”.
In this case, it is unnecessary to inspect DTC
P0121.
Replace throttle position sensor.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.
[T3D0] and [T3E0].>
WIRING DIAGRAM:
OBD0183
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OBD0191
I: DTC P0125
—INSUFFICIENT COOLANT TEMPERATURE
FOR CLOSED LOOP FUEL CONTROL
(TW
—CL)—
DESCRIPTION:
Refer to“F: DTC P0115—ENGINE COOLANT TEM-
PERATURE SENSOR CIRCUIT MALFUNCTION—
[T11F0]”.
DTC DETECTING CONDITION:
Two consecutive trips with fault
TROUBLE SYMPTOM:
Engine would not return to idling.
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Page 1376 of 2248
1.Check DTC P0115 on display.
No
Ye s
Inspect DTC P0115 using“11. Diagnostics Chart
with Trouble Code [T1100]”.
In this case, it is unnecessary to inspect DTC
P0125.
Replace engine coolant temperature sensor.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.
[T3D0] and [T3E0].>
WIRING DIAGRAM:
OBD0174
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