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OBD0689A
2CHECK INPUT SIGNAL FOR ECM. (USING
VOLTAGE METER AND SUBARU SELECT
MONITOR.)
Measure voltage between ECM and body while engine is
idling.
: Connector & terminal
(B84) No. 26—Body/0.3 V, or less
: Go to step 3.
: Go to next.
G2M0527
: Is the voltage more than 0.3 V while shaking
harness and connector of ECM and monitor-
ing the value with Subaru select monitor?
: Repair poor contact in ECM connector.
: Replace ECM with a new one.
B2M0623A
3CHECK POWER SUPPLY TO MASS AIR
FLOW SENSOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from mass air flow sensor.
3) Turn ignition switch to ON.
4) Measure voltage between mass air flow sensor connec-
tor and body.
: Connector & terminal
(B3) No. 1—Body/10 V, or more
: Go to step 4.
: Repair open circuit of harness between main relay
connector and mass air flow sensor connector.
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OBD0690A
4CHECK HARNESS CONNECTOR BETWEEN
ECM AND MASS AIR FLOW SENSOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from ECM.
3) Measure resistance of harness connector between
ECM and mass air flow sensor.
: Connector & terminal
1(B84) No. 26—(B3) No. 4/10Ω, or less
2(B84) No. 46—(B3) No. 3/10Ω, or less
3(B84) No. 25—(B3) No. 2/10Ω, or less
: Replace mass air flow sensor with a new one.
: Repair poor contact and open circuit of harness
between ECM and mass air flow sensor connec-
tor.
G2M0527
5
CHECK HARNESS.
1) Turn ignition switch to OFF.
2) Disconnect connector from mass air flow sensor.
3) Connect Subaru Select Monitor or OBD-II General
Scan Tool to data link connector.
4) Turn ignition switch to ON.
5) Read data on Subaru select monitor or OBD-II general
scan tool.
Subaru Select Monitor
Designate mode using function key.
Function mode: F08
: Is the value more than 5 V?
: Repair short circuit of harness between mass air
flow sensor and ECM.
: Go to next.
: Is there poor contact in mass air flow sensor
connector?
: Repair poor contact in mass air flow sensor con-
nector.
: Replace mass air flow sensor.
OBD-II general scan tool
For detailed operation procedures, refer to OBD-II General
Scan Tool Instruction Manual.
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OBD0152
C: DTC P0101
—MASS AIR FLOW SENSOR CIRCUIT
RANGE/PERFORMANCE PROBLEM (QA
—R)
—
DESCRIPTION:
Refer to“B: DTC P0100—MASS AIR FLOW SENSOR
CIRCUIT MALFUNCTION—[T11B0]”.
DTC DETECTING CONDITION:
Two consecutive trips with fault
TROUBLE SYMPTOM:
Erroneous idling
Engine stalls.
Poor driving performance
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1.Check DTC P0100 on display.
No
Ye s
Inspect DTC P0100 using“11. Diagnostics
Chart with Trouble Code [T1100]”.
In this case, it is unnecessary to inspect DTC
P0101.
Replace mass air flow sensor.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.
[T3D0] and [T3E0].>
WIRING DIAGRAM:
LHD model
OBD0144
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WIRING DIAGRAM:
RHD model
B2M0448
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OBD0154
D: DTC P0105
—PRESSURE SENSOR CIRCUIT
MALFUNCTION (P
—S)—
OBD0155A
DESCRIPTION:
The pressure sensor is used in AT vehicles. It is located in
the engine compartment, at the front of the right-hand sus-
pension. It consists of a solenoid, which switches between
the atmospheric pressure and suction pressure lines and a
pressure sensor. This arrangement allows either pressure
line to be monitored.
A sensor output signal is sent to the ECM to diagnose the
EGR system and evaporative emission control system.
(The pressure sensor is not used in MT vehicles.)
DTC DETECTING CONDITION:
Immediately at fault recognition
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1.Check transmission type.
AT
MT
Check AT/MT identification circuit.
[T11BN0].>
2.Connect Subaru Select Monitor or the OBD-II
general scan tool, and read data.
3.Check input signal for ECM. (Using voltage
meter and Subaru Select Monitor.)
4.Check harness connector between ECM and
pressure sensor.
5.Check harness connector between ECM and
pressure sensor.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.
[T3D0] and [T3E0].>
WIRING DIAGRAM:
LHD model
B2M0624
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WIRING DIAGRAM:
RHD model
B2M0449
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11. Diagnostics Chart with Trouble Code