1997 SUBARU LEGACY obd

OBD0315
AO: DTC P0400
—EXHAUST GAS RECIRCULATION FLOW
MALFUNCTION—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
TROUBLE SYMPTOM:

Poor driving performance on low engine speed
WIRING DIAGRAM:
B2M1093
CAUTION:
Before confirmation of actual driving pattern, conduct
CLEAR MEMORY and INSPECTION MODES.

232
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

10AO1
CHECK ENGINE/TRANSMISSION TYPE.
: Is engine/transmission type 2200 cc/MT?
: Check AT/MT identification circuit. [T10DD0].>
: Go to step10AO2.
10AO2CHECK DTC P0106, P0107, P0108, P0403,
P1102, P1122 OR P1421 ON DISPLAY.
: Does the Subaru select monitor or OBD-II
general scan tool indicate DTC P0106,
P0107, P0108, P0403, P1102, P1122 or
P1421?
:
Inspect DTC P0106, P0107, P0108, P0403,
P1102, P1122 or P1421 using“10. Diagnostics
Chart with Trouble Code”.

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 step10AO3.
233
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M1094A
B2M1284A
B2M0647B
10AO3
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
CONFIRMATION OF ACTUAL DRIVING
PATTERN.
: Go to step10AO4.
OBD0005B
10AO4
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”.
: Go to next step 4).
: Replace EGR solenoid valve.
234
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

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. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0323
AP: DTC P0403
—EXHAUST GAS RECIRCULATION CIRCUIT
LOW INPUT—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
TROUBLE SYMPTOM:

Poor driving performance on low engine speed
WIRING DIAGRAM:
B2M1096
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

237
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

10AP1
CHECK ENGINE/TRANSMISSION TYPE.
: Is engine/transmission type 2200 cc/MT?
: Check AT/MT identification circuit. [T10DD0].>
: Go to step10AP2.
B2M0566A
10AP2
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 next.
: Go to step10AP3.
: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. (However, the pos-
sibility of poor contact still remains.)
NOTE:
In this case, repair the following:

Poor contact in EGR solenoid valve connector

Poor contact in ECM connector

Poor contact in coupling connector (B21)
OBD0678A
10AP3CHECK 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 ground short circuit in harness between
ECM and EGR solenoid valve connector.
: Go to next step 4).
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

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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2-7ON-BOARD DIAGNOSTICS II SYSTEM
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