check engine SUBARU LEGACY 1995 Service Repair Manual

DTC DETECTING CONDITION:

Immediately at fault recognition
TROUBLE SYMPTOM:

Engine stalls.

Failure of engine to start
1.Check harness.
2.Check crankshaft position sensor.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

WIRING DIAGRAM:
OBD0295

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11. Diagnostics Chart with Trouble Code

OBD0317A

The EGR valve is situated between the exhaust manifold
and intake manifold. After opening EGR solenoid valve,
EGR valve is opened for receiving throttle port pressure on
diaphragm. Then, part of the exhaust gas is recirculated
into intake manifold.
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Poor driving performance on low engine speed
1.Check transmission type.
AT
MT
Check AT/MT identification circuit. [T11BN0].>
2.Check DTC P0105, P0106, P0403, P1102 on
display.

3.Check vacuum hose.
4.Check operation of EGR system.
Confirmation of actual driving
pattern
CAUTION:
Before confirmation of actual driving pattern, conduct
CLEAR MEMORY and INSPECTION MODES. [T3D0] and [T3E0].>




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11. Diagnostics Chart with Trouble Code

3
CHECK VACUUM HOSE.
: Check vacuum hoses for disconnection,
leakage and clogging.
: Check and repair the following items.

Two lines of pipes and hoses running between
throttle body and BPT

Pipe and hose line connecting BPT and EGR
solenoid valve

Hose between EGR solenoid valve and EGR
valve

BPT pressure transmitting hose
: Go to step 4.
4
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?
: Replace EGR solenoid valve.
: Go to next step.
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.
7) Start the engine.
: Open throttle valve by 5 to 10 degrees and
visually check EGR valve operation.
: 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 PATTERN.
NOTE:
If malfunction is detected again in the confirmation of actual
driving pattern, EGR valve is faulty. Go to next
.
: Go to next.
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11. Diagnostics Chart with Trouble Code

: 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.
: Replace EGR valve. And go toCONFIRMA-
TION OF ACTUAL DRIVING PATTERN.
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.
5) Designate mode using function key.
Function mode: FA4
6) Drive at 55±3 MPH (88±5 km/h) until the LED No. 5 is
turned 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.
7) Designate mode using function key.
Function mode: FB0
8) Confirm the“No trouble”indication on Subaru select
monitor.
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11. Diagnostics Chart with Trouble Code

OBD0323
AC: DTC P0403
—EXHAUST GAS RECIRCULATION CIRCUIT
MALFUNCTION (EGRSOL)—
OBD0324A
DESCRIPTION:
The EGR solenoid valve is situated between the BPT and
EGR valve. EGR solenoid valve is opened by a signal
emitted from the ECM. Therefore, throttle port pressure is
transmitted to diaphragm of EGR valve.
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Poor driving performance on low engine speed
1.Check transmission type.
AT
MT
Check AT/MT identification circuit.
2.Check output signal from ECM.

3.Check harness.
4.Check harness.
5.Check EGR solenoid valve.
6.Check power supply to EGR solenoid valve.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES. [T3D0] and [T3E0].>




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11. Diagnostics Chart with Trouble Code

1
CHECK AIR INTAKE SYSTEM.
1) Turn ignition switch to ON.
2) Start engine, and idle it.
3) Check intake manifold, idle air control solenoid valve
and throttle body for loose installation and gasket for
cracks.
4) Check by-pass hoses for loose connections and cracks.
5) Check vacuum hoses for disconnections.
OBD0362A
2
CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and body.
: Connector & terminal
(B84) No. 11—Body / 3 V, or more
(B84) No. 12—Body / 3 V, or more
: Go to step 4.
: Go to the next step.
OBD0362A
3) Turn ignition switch to OFF.
4) Disconnect connector from idle air control solenoid
valve.
5) Turn ignition switch to ON.
6) Measure voltage between ECM and body.
: Connector & terminal
(B84) No. 11—Body / 10 V, or more
(B84) No. 12—Body / 10 V, or more
: Repair short circuit of harness and replace ECM.
: Go to next.
: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Go to step 3.
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11. Diagnostics Chart with Trouble Code

OBD0370
AI: DTC P0506
—IDLE CONTROL SYSTEM RPM LOWER
THAN EXPECTED (ISC
—L)—
DESCRIPTION:
Refer to“AH: DTC P0505—IDLE CONTROL SYSTEM
MALFUNCTION—[T11AH0]”.
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Engine is difficult to start.

Engine does not start.

Erroneous idling

Engine stalls.
1.Check DTC P0505 on display.
No
Ye s

Inspect DTC P0505 using“11. Diagnostics Chart
with Trouble Code [T1100]”.

In this case, it is unnecessary to inspect DTC
P0506.
2.Check air intake system.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES. [T3D0] and [T3E0].>

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11. Diagnostics Chart with Trouble Code

2
CHECK AIR INTAKE SYSTEM.
1) Turn ignition switch to ON.
2) Start engine, and idle it.
: Is clogging the by-pass line between by-
pass hose and intake duct?
: Repair the by-pass line.
: Replace idle air control solenoid valve.
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OBD0371
AJ: DTC P0507
—IDLE CONTROL SYSTEM RPM HIGHER
THAN EXPECTED (ISC
—H)—
DESCRIPTION:
Refer to“AH: DTC P0505—IDLE CONTROL SYSTEM
MALFUNCTION—[T11AH0]”.
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Engine keeps running at higher revolution than specified
idling revolution.
1.Check DTC P0505 on display.
No
Ye s

Inspect DTC P0505 using“11. Diagnostics Chart
with Trouble Code [T1100]”.

In this case, it is unnecessary to inspect DTC
P0507.
2.Check air intake system.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES. [T3D0] and [T3E0].>

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2
CHECK AIR INTAKE SYSTEM.
1) Turn ignition switch to ON.
2) Start engine, and idle it.
:
Check intake manifold, idle air control
solenoid valve and throttle body for loose
installation and gasket for cracks.

Check by-pass hose for loose connection
and cracks.

Check vacuum hoses for disconnections.
: Repair air suction and leaks.
: Replace idle air control solenoid valve.
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11. Diagnostics Chart with Trouble Code