SUBARU LEGACY 1996 Service Repair Manual

WIRING DIAGRAM:

RHD Model
B2M0792
10AD1
CHECK TRANSMISSION TYPE.
: Is transmission type AT?
: Go to step10AD2.
: Check AT/MT identification circuit. [T10BW0].>
10AD2CHECK DTC P0105, P0106, P0403, P1102
ON DISPLAY.
: Does the Subaru select monitor or OBD-II
general scan tool indicate DTC P0105,
P0106, P0403 or P1102?
:
Inspect DTC P0105, P0106, P0403 or P1102
using“10. Diagnostics Chart with Trouble Code
2-7 [T1000]”.

Manually check that EGR valve diaphragm is
not stuck.
WARNING:
Be careful when checking EGR valve, since it may be
extremely hot.
NOTE:
In this case, it is not necessary to inspect DTC P0400.
After checking the above item, go to
CONFIRMATION
OF ACTUAL DRIVING PATTERN.
: Go to step10AD3.
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10. Diagnostics Chart with Trouble Code

B2M0647A
10AD3
CHECK VACUUM LINE.
: Is there a fault in vacuum line?
NOTE:
Check the following items.

Disconnection, leakage and clogging of the two vacuum
hoses and pipes between throttle body and BPT

Disconnection, leakage and clogging of the vacuum
hose and pipe between EGR solenoid valve and BPT

Disconnection, leakage and clogging of the vacuum
hose between EGR solenoid valve and EGR valve

Disconnection, leakage and clogging of BPT pressure
transmitting hose
: Repair or replace hoses and pipes.
And after the checking and repairing, go to
CON-
FIRMATION OF ACTUAL DRIVING
PATTERN.
: Go to step10AD4.
OBD0005B
10AD4
CHECK OPERATION OF EGR SYSTEM.
1) Turn ignition switch to OFF.
2) Connect the test mode connector.
3) Turn ignition switch to ON.
: Does EGR solenoid valve produce operating
sound?
NOTE:
EGR control solenoid valve operation check can also be
executed using Subaru Select Monitor (Function mode:
FD05). For the procedure, refer to“COMPULSORY VALVE
OPERATION CHECK MODE”2-7 [T3F0].
: Go to next step 4).
: Replace EGR solenoid valve.
4) Turn ignition switch to OFF.
5) Disconnect connector from EGR solenoid valve.
6) Connect 12 V battery’s ground
terminal to one ter-
minal of the EGR solenoid valve. Then connect 12 V bat-
tery’sterminal to the other terminal of it.
CAUTION:
Do not use the 12 V battery installed in the vehicle,
because the electrical system may be damaged.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

7) Start the engine.
: Does EGR valve operate at a throttle valve
opening of 5 to 10 degrees with visually
check?
: Possibly EGR valve malfunction may be due to
freezing or clogging by foreign matter. At this point
in time do not replace EGR valve, since it is not
faulty. And after the checking, go to
CONFIR-
MATION OF ACTUAL DRIVING PAT-
TERN.
NOTE:
If malfunction is detected again in the confirmation of actual
driving pattern, EGR valve is faulty. Go to next
.
: Go to next.
: Is there clogging in the gas outlets of intake
manifold or cylinder head, checking by
breathing into the outlets?
: Repair or replace intake manifold or cylinder
head. And go to
CONFIRMATION OF
ACTUAL DRIVING PATTERN.
: Clean EGR valve. And go toCONFIRMATION
OF ACTUAL DRIVING PATTERN.
CAUTION:
Do not use solvent when cleaning EGR valve
assembly, as it can damage diaphragm.
NOTE:

Remove and blow away the exhaust deposits. Make
sure the valve operates smoothly and the valve seat area
is completely cleaned.

Replace EGR valve as required.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

OBD0145A
CONFIRMATION OF ACTUAL DRIVING
PATTERN.
1) Conduct CLEAR MEMORY and INSPECTION MODES.

2) Connect Subaru select monitor to its data link connec-
tor.
3) Start and warm-up the engine until the radiator fan
makes one complete rotation. (All accessory switches are
OFF.)
4) Turn Subaru select monitor switch to ON.
G3M0152
5) Designate mode using function key.
Function mode: FA4
B2M0564
6) Drive at 88±5 km/h (55±3 MPH) until the LED No. 2
comes on.
NOTE:
Keep the throttle valve opening at the same degree, since
diagnosis will be interrupted when the opening varies.
Diagnosis starts in 190 seconds after starting engine and
takes 4 seconds.
Put the gear to“D”range for the diagnosis.
H2M1206
7) Designate mode using function key.
Function mode: FB0
8) Confirm the“No trouble”indication on Subaru select
monitor.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

OBD0323
AE: DTC P0403
—EXHAUST GAS RECIRCULATION CIRCUIT
MALFUNCTION (EGRSOL)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Poor driving performance on low engine speed
10AE1Check transmission type.
10AE2Check output signal from ECM.

10AE3Check harness between EGR solenoid valve
and ECM connector.
10AE4Check harness between EGR solenoid valve
and ECM connector.
10AE5Check EGR solenoid valve.
10AE6Check power supply to EGR solenoid valve.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.





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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

WIRING DIAGRAM:

LHD Model
B2M0565
228
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

WIRING DIAGRAM:

RHD Model
B2M0793
229
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

10AE1
CHECK TRANSMISSION TYPE.
: Is transmission type AT?
: Go to step10AE2.
: Check AT/MT identification circuit. [T10BW0].>
B2M0566A
10AE2
CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 71 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Go to step10AE3.
: Go to step10AE4.
B2M0566A
10AE3CHECK HARNESS BETWEEN EGR
SOLENOID VALVE AND ECM CONNEC-
TOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from EGR solenoid valve.
3) Turn ignition switch to ON.
4) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 71 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Repair short circuit in harness and replace ECM.
NOTE:
The harness between ECM and EGR solenoid valve is in
short circuit.
: Go to next step 5).
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

OBD0327
5) Turn ignition switch to OFF.
6) Measure resistance between EGR solenoid valve ter-
minals.
: Terminals
No. 1—No. 2:
Is the resistance less than 1Ω?
: Replace EGR solenoid valve and ECM.
: Go to next.
: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Replace ECM.
OBD0678A
10AE4CHECK HARNESS BETWEEN EGR
SOLENOID VALVE AND ECM CONNEC-
TOR.
1) Turn ignition switch to OFF.
2) Disconnect connectors from EGR solenoid valve and
ECM.
3) Measure resistance of harness between EGR solenoid
valve connector and engine ground.
: Connector & terminal
(E18) No. 2—Engine ground:
Is the resistance less than 10Ω?
: Repair short circuit in harness between ECM and
EGR solenoid valve connector.
: Go to next step 4).
B2M0567A
4) Measure resistance of harness between ECM and EGR
solenoid valve connector.
: Connector & terminal
(B84) No. 71—(E18) No. 2:
Is the resistance less than 1Ω?
: Go to step10AE5.
: Repair open circuit in harness between ECM and
EGR solenoid valve connector.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostics Chart with Trouble Code

OBD0327
10AE5
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 step10AE6.
: Replace EGR solenoid valve.
OBD0328A
10AE6CHECK 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. Diagnostics Chart with Trouble Code