engine SUBARU LEGACY 1997 Service Repair Manual

B2M0567A
4) Measure resistance of harness between ECM and EGR
solenoid valve connector.
: Connector & terminal
(B84) No. 71—(E18) No. 2:
Is the voltage less than 1Ω?
: Go to step10AP4.
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between EGR solenoid valve
and ECM connector

Poor contact in coupling connector (B21)

Poor contact in EGR solenoid valve connector

Poor contact in ECM connector
OBD0327
10AP4
CHECK EGR SOLENOID VALVE.
Measure resistance between EGR solenoid valve termi-
nals.
: Terminals
No. 1—No. 2:
Is the resistance between 10 and 100Ω?
: Go to step10AP5.
: Replace EGR solenoid valve.
OBD0328A
10AP5CHECK POWER SUPPLY TO EGR SOLE-
NOID VALVE.
1) Turn ignition switch to ON.
2) Measure voltage between EGR solenoid valve and
engine ground.
: Connector & terminal
(E18) No. 1 (+)—Engine ground ():
Is the voltage more than 10 V?
: Go to next.
: Repair open circuit in harness between main relay
and EGR solenoid valve connector.
: Is there poor contact in EGR solenoid valve
connector?
: Repair poor contact in EGR solenoid valve con-
nector.
: Contact with SOA service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
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10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0329
AQ: DTC P0420
—CATALYST SYSTEM EFFICIENCY BELOW
THRESHOLD—
DTC DETECTING CONDITION:

Immediately at fault recognition (2200 cc Federal spec.
vehicles only)

Two consecutive driving cycles with fault
TROUBLE SYMPTOM:

Engine stalls.

Idle mixture is out of specifications.
WIRING DIAGRAM:
B2M1097
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

240
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M0570A
10AT1
CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 72 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. Contact with SOA
service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
: Go to step10AT2.
OBD0680A
10AT2CHECK HARNESS BETWEEN PURGE
CONTROL SOLENOID VALVE AND ECM
CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connectors from purge control solenoid
valve and ECM.
3) Measure resistance of harness between purge control
solenoid valve connector and engine ground.
: Connector & terminal
(E4) No. 2—Engine ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in harness between
ECM and purge control solenoid valve connector.
: Go to next step 4).
B2M0571A
4) Measure resistance of harness between ECM and
purge control solenoid valve of harness connector.
: Connector & terminal
(B84) No. 72—(E4) No. 2:
Is the resistance less than 1Ω?
: Go to step10AT3.
: Repair open circuit in harness between ECM and
purge control solenoid valve connector.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0338
10AT3CHECK PURGE CONTROL SOLENOID
VA LV E .
1) Remove purge control solenoid valve.
2) Measure resistance between purge control solenoid
valve terminals.
: Terminals
No. 1—No. 2:
Is the resistance between 10 and 100Ω?
: Go to step10AT4.
: Replace purge control solenoid valve.
OBD0339A
10AT4CHECK POWER SUPPLY TO PURGE
CONTROL SOLENOID VALVE.
1) Turn ignition switch to ON.
2) Measure voltage between purge control solenoid valve
and engine ground.
: Connector & terminal
(E4) No. 1 (+)—Engine ground ():
Is the voltage more than 10 V?
: Go to next.
: Repair open circuit in harness between main relay
and purge control solenoid valve connector.
: Is there poor contact in purge control sole-
noid valve connector?
: Repair poor contact in purge control solenoid
valve connector.
: Contact with SOA service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
250
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

H2M1414B
10AZ3CHECK INPUT SIGNAL FOR ECM.
(USING VOLTAGE METER AND SUBARU
SELECT MONITOR.)
1) Turn ignition switch to ON. (Engine OFF)
2) Measure voltage between ECM connector and chassis
ground.
: Connector & terminal
(B84) No. 27 (+)—Chassis ground ():
Is the voltage less than 0.12 V?
: Go to step10AZ4.
: Go to next.
H2M1327
: Does the value change less than 0.12 V by
shaking harness and connector of ECM
while monitoring the value with Subaru
Select Monitor?

Subaru Select Monitor
Designate mode using function key.
Function mode: F45

F45: Fuel level sensor output signal is indicated.
: Repair poor contact in ECM connector.
: 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.
NOTE:
In this case, repair the following:

Poor contact in fuel pump connector

Poor contact in combination meter connector

Poor contact in ECM connector

Poor contact in coupling connector (i3, B99, B22, B98
and R57)
G2M0340
10AZ4CHECK HARNESS BETWEEN ECM, COM-
BINATION METER AND FUEL PUMP
CONNECTOR.
1) Turn ignition switch to OFF.
2) Remove fuel pump access hole lid located on the right
rear of trunk compartment floor (Sedan) or luggage com-
partment floor (Wagon).
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

H2M1414B
10BA3CHECK INPUT SIGNAL FOR ECM.
(USING VOLTAGE METER AND SUBARU
SELECT MONITOR.)
1) Turn ignition switch to ON. (Engine OFF)
2) Measure voltage between ECM connector and chassis
ground.
: Connector & terminal
(B84) No. 27 (+)—Chassis ground ():
Is the voltage more than 4.75 V?
: Go to step10BA4.
: 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.
NOTE:
In this case, repair the following:

Poor contact in fuel pump connector

Poor contact in combination meter connector

Poor contact in ECM connector

Poor contact in coupling connector (i3, B99, B22, B98
and R57)
G2M0340
10BA4
CHECK FUEL LEVEL SENSOR.
1) Turn ignition switch to OFF.
2) Remove fuel pump access hole lid located on the right
rear of trunk compartment floor (Sedan) or luggage com-
partment floor (Wagon).
B2M0935
3) Disconnect connector from fuel pump.
4) Measure resistance between connector terminals of
fuel pump.
: Terminals
No. 3—No. 5:
Is the resistance less than 100Ω?
: Go to step10BA5.
: Replace fuel sending unit.
G2M0863
10BA5
CHECK FUEL SUB LEVEL SENSOR.
1) Remove service hole cover located on the left rear of
trunk compartment floor (Sedan) or luggage compartment
floor (Wagon).
277
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0358
BC: DTC P0505
—IDLE CONTROL SYSTEM MALFUNCTION
—
DTC DETECTING CONDITION:

Immediately at fault recognition
TROUBLE SYMPTOM:

Erroneous idling

Engine stalls.

Engine breathing
WIRING DIAGRAM:
B2M1311
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

283
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

10BC1
CHECK AIR INTAKE SYSTEM.
1) Turn ignition switch to ON.
2) Start engine, and idle it.
: Is there a fault in air intake system?
NOTE:
Check the following items.

Loose installation of intake manifold, idle air control sole-
noid valve and throttle body

Cracks of intake manifold gasket, idle air control sole-
noid valve gasket and throttle body gasket

Loose connections and cracks of idle air control solenoid
valve by-pass hoses

Disconnections of vacuum hoses
: Repair or replace air intake system.
: Go to step10BC2.
B2M0576A
10BC2
CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 13 (+)—Chassis ground ():
Is the voltage more than 3 V?
: Go to next.
: Go to step10BC4.
: Connector & terminal
(B84) No. 14 (+)—Chassis ground ():
Is the voltage more than 3 V?
: Go to next step 3).
: Go to step10BC4.
284
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M0578A
10BC4CHECK POWER SUPPLY TO IDLE AIR
CONTROL SOLENOID VALVE.
1) Turn ignition switch to OFF.
2) Disconnect connector from idle air control solenoid
valve.
3) Turn ignition switch to ON.
4) Measure voltage between idle air control solenoid valve
and engine ground.
: Connector & terminal
(E7) No. 2 (+)—Engine ground ():
Is the voltage more than 10 V?
: Go to step10BC5.
: Repair open circuit in harness between idle air
control solenoid valve and main relay connector.
B2M0579A
10BC5CHECK HARNESS BETWEEN ECM AND
IDLE AIR CONTROL SOLENOID VALVE
CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from ECM.
3) Measure resistance of harness between ECM and idle
air control solenoid valve connector.
: Connector & terminal
(B84) No. 14—(E7) No. 1:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between ECM and
idle air control solenoid valve connector.
: Connector & terminal
(B84) No. 13—(E7) No. 3:
Is the resistance less than 1Ω?
: Go to next step 4).
: Repair open circuit in harness between ECM and
idle air control solenoid valve connector.
B2M0580A
4) Measure resistance of harness between ECM and
chassis ground.
: Connector & terminal
(B84) No. 13—Chassis ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in harness between
ECM and idle air control solenoid valve connector.
: Go to next.
287
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M1104
BD: DTC P0506
—IDLE CONTROL SYSTEM RPM LOWER
THAN EXPECTED—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
TROUBLE SYMPTOM:

Engine is difficult to start.

Engine does not start.

Erroneous idling

Engine stalls.
WIRING DIAGRAM:
B2M1311
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

289
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles