1997 SUBARU LEGACY ignition

8E1CHECK OPERATING SOUND OF FUEL
PUMP.
Make sure that fuel pump is in operation for two seconds
when turning ignition switch to ON.
: Does fuel pump produce operating sound?
NOTE:
Fuel pump operation check can also be executed using
Subaru Select Monitor (Function mode: FD01).
For the procedure, refer to“COMPULSORY VALVE
OPERATION CHECK MODE”.
: Check fuel injector circuit.
: Go to step8E2.
OBD0132A
8E2CHECK GROUND CIRCUIT OF FUEL
PUMP.
1) Turn ignition switch to OFF.
2) Disconnect connector from fuel pump.
3) Measure resistance of harness connector between fuel
pump and chassis ground.
: Connector & terminal
(R58) No. 4—Chassis ground:
Is the resistance less than 5Ω?
: Go to step8E3.
: Repair open circuit in fuel pump ground circuit.
OBD0133A
8E3
CHECK POWER SUPPLY TO FUEL PUMP.
1) Turn ignition switch to ON.
2) Measure voltage of power supply circuit between fuel
pump connector and chassis ground.
: Connector & terminal
(R58) No. 1 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Replace fuel pump.
: Go to step8E4.
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8. Diagnostics for Engine Starting Failure

B2M0526A
8E4CHECK HARNESS BETWEEN FUEL
PUMP AND FUEL PUMP RELAY CON-
NECTOR.
1) Turn ignition switch to OFF.
2) Measure resistance of harness connector between fuel
pump and fuel pump relay.
: Connector & terminal
(R58) No. 1—(B46) No. 4:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between fuel pump
and fuel pump relay connector.
: Connector & terminal
(R58) No. 1—Chassis ground:
Is the resistance more than 1 MΩ?
: Go to step8E5.
: Repair short circuit in harness between fuel pump
and fuel pump relay connector.
G2M0461
8E5
CHECK FUEL PUMP RELAY.
1) Disconnect connectors from fuel pump relay and main
relay.
2) Remove fuel pump relay and main relay with bracket.
3) Connect battery to fuel pump relay connector terminals
No. 1 and No. 3.
4) Measure resistance between connector terminals of
fuel pump relay.
: Terminals
No. 2—No. 4:
Is the resistance less than 10Ω?
: Go to step8E6.
: Replace fuel pump relay.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
8. Diagnostics for Engine Starting Failure

8F1CHECK OPERATING SOUND OF FUEL
PUMP.
Make sure that fuel pump is in operation for two seconds
when turning ignition switch to ON.
: Does fuel pump produce operating sound?
NOTE:
Fuel pump operation check can also be executed using
Subaru Select Monitor (Function mode: FD01).
For the procedure, refer to“COMPULSORY VALVE
OPERATION CHECK MODE”.
: Check fuel injector circuit.
: Go to step8F2.
OBD0132A
8F2CHECK GROUND CIRCUIT OF FUEL
PUMP.
1) Turn ignition switch to OFF.
2) Disconnect connector from fuel pump.
3) Measure resistance of harness connector between fuel
pump and chassis ground.
: Connector & terminal
(R58) No. 4—Chassis ground:
Is the resistance less than 5Ω?
: Go to step8F3.
: Repair open circuit in fuel pump ground circuit.
OBD0133A
8F3
CHECK POWER SUPPLY TO FUEL PUMP.
1) Turn ignition switch to ON.
2) Measure voltage of power supply circuit between fuel
pump connector and chassis ground.
: Connector & terminal
(R58) No. 1 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Replace fuel pump.
: Go to step8F4.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
8. Diagnostics for Engine Starting Failure

B2M0526A
8F4CHECK HARNESS BETWEEN FUEL
PUMP AND FUEL PUMP RELAY CON-
NECTOR.
1) Turn ignition switch to OFF.
2) Measure resistance of harness connector between fuel
pump and fuel pump relay.
: Connector & terminal
(R58) No. 1—(B46) No. 4:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between fuel pump
and fuel pump relay connector.
: Connector & terminal
(R58) No. 1—Chassis ground:
Is the resistance more than 1 MΩ?
: Go to step8F5.
: Repair short circuit in harness between fuel pump
and fuel pump relay connector.
G2M0461
8F5
CHECK FUEL PUMP RELAY.
1) Disconnect connectors from fuel pump relay and main
relay.
2) Remove fuel pump relay and main relay with bracket.
3) Connect battery to fuel pump relay connector terminals
No. 1 and No. 3.
4) Measure resistance between connector terminals of
fuel pump relay.
: Terminals
No. 2—No. 4:
Is the resistance less than 10Ω?
: Go to step8F6.
: Replace fuel pump relay.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
8. Diagnostics for Engine Starting Failure

9. General Diagnostic Table
A: GENERAL DIAGNOSTICS TABLE WITH
NONCONFORMITY SYMPTOM FOR ENGINE
NOTE:
Malfunction of parts other than those listed is also possible.

Symptom Problem parts
1. Engine stalls during idling.1) Idle air control solenoid valve
2) Mass air flow sensor
3) Ignition parts (*1)
4) Engine coolant temperature sensor (*2)
5) Crankshaft position sensor (*3)
6) Camshaft position sensor (*3)
7) EGR valve
8) Fuel injection parts (*4)
2. Rough idling1) Idle air control solenoid valve
2) Mass air flow sensor
3) Engine coolant temperature sensor (*2)
4) Ignition parts (*1)
5) Air intake system (*5)
6) Fuel injection parts (*4)
7) Throttle position sensor
8) Crankshaft position sensor (*3)
9) Camshaft position sensor (*3)
10) EGR valve
11) Oxygen sensor
12) Fuel pump and fuel pump relay
3. Engine does not return to idle.1) Idle air control solenoid valve
2) Engine coolant temperature sensor
3) Accelerator cable (*6)
4) Throttle position sensor
5) Mass air flow sensor
4. Poor acceleration1) Mass air flow sensor
2) Throttle position sensor
3) Fuel injection parts (*4)
4) Fuel pump and fuel pump relay
5) Engine coolant temperature sensor (*2)
6) Crankshaft position sensor (*3)
7) Camshaft position sensor (*3)
8) A/C switch and A/C cut relay
9) Engine torque control signal circuit
10) Ignition parts (*1)
5. Engine stalls or engine sags or hesitates at
acceleration.1) Mass air flow sensor
2) Engine coolant temperature sensor (*2)
3) Crankshaft position sensor (*3)
4) Camshaft position sensor (*3)
5) Purge control solenoid valve
6) EGR valve
7) Fuel injection parts (*4)
8) Throttle position sensor
9) Fuel pump and fuel pump relay
6. Surge1) Mass air flow sensor
2) Engine coolant temperature sensor (*2)
3) Crankshaft position sensor (*3)
4) Camshaft position sensor (*3)
5) EGR valve
6) Fuel injection parts (*4)
7) Throttle position sensor
8) Fuel pump and fuel pump relay
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9. General Diagnostic Table

Symptom Problem parts
7. Spark knock1) Mass air flow sensor
2) Engine coolant temperature sensor
3) Knock sensor
4) Fuel injection parts (*4)
5) Fuel pump and fuel pump relay
8. After burning in exhaust system1) Mass air flow sensor
2) Engine coolant temperature sensor (*2)
3) Fuel injection parts (*4)
4) Fuel pump and fuel pump relay
*1: Check ignitor, ignition coil and spark plug.
*2: Indicate the symptom occurring only in cold temperatures.
*3: Ensure the secure installation.
*4: Check fuel injector, fuel pressure regulator and fuel filter.
*5: Inspect air leak in air intake system.
*6: Adjust accelerator cable.
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9. General Diagnostic Table

OBD0145A
10C1CONNECT 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
the OBD-II general scan tool switch to ON.
4) Start engine.
B2M0481
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F06

F06: Mass air flow and voltage input from mass air flow
sensor are shown on display at the same time.
: Is the value equal to or more than 1.3 g/sec
or 0.3 V and equal to or less than 250 g/sec
or 5.0 V in function mode F06?
Probable cause: Poor connect of connectors, circuit and
grounding line.
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. A temporary poor
contact of the connector or harness may be the
cause. Repair harness or connector in the mass
air flow sensor.
NOTE:
In this case, repair the following:

Open or ground short circuit in harness between mass
air flow sensor and ECM connector

Poor contact in mass air flow sensor or ECM connector
: Go to step10C2.
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10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M0532A
10C2CHECK INPUT SIGNAL FOR ECM.
(USING VOLTAGE METER AND SUBARU
SELECT MONITOR.)
Measure voltage between ECM connector and chassis
ground while engine is idling.
: Connector & terminal
(B84) No. 5 (+)—Chassis ground ():
Is the voltage less than 0.3 V?
: Go to step10C3.
: Go to next.
B2M0481
: Does the voltage change more than 0.3 V by
shaking harness and connector of ECM
while monitoring the value with Subaru
select monitor?
: Repair poor contact in ECM connector.
: Contact with SOA service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
B2M0645A
10C3CHECK 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 engine ground.
: Connector & terminal
(B3) No. 1 (+)—Engine ground ():
Is the voltage more than 10 V?
: Go to step10C4.
: Repair open circuit in harness between main relay
and mass air flow sensor connector.
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10. Diagnostic Chart with Trouble Code for LHD Vehicles