sensor SUBARU LEGACY 1997 Service Repair Manual

10BP2CHECK THROTTLE POSITION SENSOR
CIRCUIT.
Check throttle position sensor circuit.
: Is there any trouble in throttle position sen-
sor circuit?
: Repair or replace throttle position sensor circuit.
: Go to step10BP3.
10BP3CHECK VEHICLE SPEED SENSOR 1 CIR-
CUIT.
Check vehicle speed sensor 1 circuit.
: Is there any trouble in vehicle speed sensor
1 circuit?
: Repair or replace vehicle speed sensor 1 circuit.
: Go to step10BP4.
10BP4CHECK VEHICLE SPEED SENSOR 2 CIR-
CUIT.
Check vehicle speed sensor 2 circuit.
: Is there any trouble in vehicle speed sensor
2 circuit?
: Repair or replace vehicle speed sensor 2 circuit.
: Go to step10BP5.
10BP5
CHECK ENGINE SPEED INPUT CIRCUIT.
Check engine speed input circuit.
: Is there any trouble in engine speed input
circuit?
: Repair or replace engine speed input circuit.
: Go to next.
: Is there poor contact in TCM connector?
: Repair poor contact in TCM connector.
: Go to next.
: Is there any mechanical trouble in automatic
transmission?
: Repair or replace automatic transmission.
: Replace TCM.
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CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

10BQ1CHECK ANY OTHER DTC (BESIDES DTC
P0740) ON DISPLAY.
: Is there any other DTC on display?
: Inspect the relevant DTC using“10. Diagnostics
Chart with Trouble Code”.
: Go to step10BQ2.
10BQ2
CHECK DUTY SOLENOID B CIRCUIT.
Check duty solenoid B circuit.
: Is there any trouble in duty solenoid B cir-
cuit?
: Repair or replace duty solenoid B circuit.
: Go to step10BQ3.
10BQ3CHECK THROTTLE POSITION SENSOR
CIRCUIT.
Check throttle position sensor circuit.
: Is there any trouble in throttle position sen-
sor circuit?
: Repair or replace throttle position sensor circuit.
: Go to step10BQ4.
10BQ4CHECK VEHICLE SPEED SENSOR 1 CIR-
CUIT.
Check vehicle speed sensor 1 circuit.
: Is there any trouble in vehicle speed sensor
1 circuit?
: Repair or replace vehicle speed sensor 1 circuit.
: Go to step10BQ5.
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10BQ5CHECK VEHICLE SPEED SENSOR 2 CIR-
CUIT.
Check vehicle speed sensor 2 circuit.
: Is there any trouble in vehicle speed sensor
2 circuit?
: Repair or replace vehicle speed sensor 2 circuit.
: Go to step10BQ6.
10BQ6
CHECK ENGINE SPEED INPUT CIRCUIT.
Check engine speed input circuit.
: Is there any trouble in engine speed input
circuit?
: Repair or replace engine speed input circuit.
: Go to step10BQ7.
10BQ7
CHECK INHIBITOR SWITCH CIRCUIT.
Check inhibitor switch circuit.
: Is there any trouble in inhibitor switch cir-
cuit?
: Repair or replace inhibitor switch circuit.
: Go to step10BQ8.
10BQ8
CHECK BRAKE LIGHT SWITCH CIRCUIT.
Check brake light switch circuit.
: Is there any trouble in brake light switch cir-
cuit?
: Repair or replace brake light switch circuit.
: Go to step10BQ9.
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10BQ9CHECK ATF TEMPERATURE SENSOR
CIRCUIT.
Check ATF temperature sensor circuit. [T7F0].>
: Is there any trouble in ATF temperature sen-
sor circuit?
: Repair or replace ATF temperature sensor circuit.
: Go to next.
: Is there poor contact in TCM connector?
: Repair poor contact in TCM connector.
: Go to next.
: Is there any mechanical trouble in automatic
transmission?
: Repair or replace automatic transmission.
: Replace TCM.
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B2M1126
CH: DTC P1141
—MASS AIR FLOW SENSOR CIRCUIT
RANGE/PERFORMANCE PROBLEM (HIGH
INPUT)—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
TROUBLE SYMPTOM:

Erroneous idling

Engine stalls.

Poor driving performance
WIRING DIAGRAM:
B2M1057
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

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10CH1CHECK DTC P0102 OR P0103 ON DIS-
PLAY.
: Does the Subaru select monitor or OBD-II
general scan tool indicate DTC P0102 or
P0103?
: Inspect DTC P0102 or P0103 using“10. Diagnos-
tics Chart with Trouble Code”. [T10A0].>
NOTE:
In this case, it is not necessary to inspect DTC P1141.
: Replace mass air flow sensor.
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B2M1127
CI: DTC P1142
—THROTTLE POSITION SENSOR CIRCUIT
RANGE/PERFORMANCE PROBLEM (LOW
INPUT)—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
TROUBLE SYMPTOM:

Erroneous idling

Engine stalls.

Poor driving performance
WIRING DIAGRAM:
B2M0540
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

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10CI1CHECK DTC P0122 OR P0123 ON DIS-
PLAY.
: Does the Subaru select monitor or OBD-II
general scan tool indicate DTC P0122 or
P0123?
: Inspect DTC P0122 or P0123 using“10. Diagnos-
tics Chart with Trouble Code”. [T10A0].>
NOTE:
In this case, it is not necessary to inspect DTC P1142.
: Replace throttle position sensor.
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10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M1128
CJ: DTC P1143
—PRESSURE SENSOR CIRCUIT
RANGE/PERFORMANCE PROBLEM (LOW
INPUT)—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
WIRING DIAGRAM:
B2M1308
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

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OBD0145A
B2M0755
10CJ1
CHECK DATA FOR CONTROL.
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 ON and Subaru Select Monitor or
the OBD-II general scan tool switch ON.
4) Start engine.
5) Read data on Subaru Select Monitor or the OBD-II gen-
eral scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F20

F20: Display shows pressure signal value sent from the
pressure sensor.
: Is the value less than 32 kPa in function
mode F20?
: Go to step10CJ3.
: Go to step10CJ2.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
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