Coolant SUBARU LEGACY 1995 Service Manual PDF

OBD0191
I: DTC P0125
—INSUFFICIENT COOLANT TEMPERATURE
FOR CLOSED LOOP FUEL CONTROL
(TW
—CL)—
DESCRIPTION:
Refer to“F: DTC P0115—ENGINE COOLANT TEM-
PERATURE SENSOR CIRCUIT MALFUNCTION—
[T11F0]”.
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Engine would not return to idling.
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11. Diagnostics Chart with Trouble Code

1.Check DTC P0115 on display.
No
Ye s

Inspect DTC P0115 using“11. Diagnostics Chart
with Trouble Code [T1100]”.

In this case, it is unnecessary to inspect DTC
P0125.
Replace engine coolant temperature sensor.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES. [T3D0] and [T3E0].>
WIRING DIAGRAM:
OBD0174

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11. Diagnostics Chart with Trouble Code

WIRING DIAGRAM:

RHD model
B2M0450
1CHECK FOR OTHER CAUSES AFFECTING
EXHAUST GAS.
: Is CO % more than 2 % after engine warm-
up?
: Check fuel system.
NOTE:
Check for use of improper fuel.
Check if engine oil or coolant level is extremely low.
: Go to step 2.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

OBD0145A
2
CHECK FRONT OXYGEN SENSOR DATA.
1) Turn ignition switch to OFF.
2) Connect the Subaru Select Monitor or the OBD-II gen-
eral scan tool to data link connector.
3) Start engine and Turn the Subaru Select Monitor and
the OBD-II general scan tool switch to ON.
4) Warm-up the engine until coolant temperature is above
70°C (160°F) and keep the engine speed at 2,000 rpm to
3,000 rpm for one minute.
5) Read data on Subaru Select Monitor or the OBD-II gen-
eral scan tool.
OBD0206
OBD0207

Subaru Select Monitor
Designate mode using function key.
Function mode: F14 or F15

F14: Front oxygen sensor max. output signal is indi-
cated.

F15: Front oxygen sensor min. output signal is indi-
cated.
: Is the difference of voltage between F14 and
F15 0.1 V, or less?
: Go to step 3.
: Replace front oxygen sensor.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

1
CHECK DTC P0130 ON DISPLAY.
: Check that Subaru Select Monitor or the
OBD-II general scan tool shows P0130.
: Go to step 2.
: Go to step 3.
2
CHECK FAILURE CAUSE OF P0130.
Perform the step 1 of DTC P0130.
: Is the failure cause of P0130 in the fuel sys-
tem?
: Check fuel system. In this case, inspection of
P0136 is not necessary.
: Go to step 3.
OBD0145A
3
CHECK REAR OXYGEN SENSOR DATA.
1) Turn ignition switch to OFF.
2) Connect Subaru Select Monitor or OBD-II general scan
tool to data link connector.
3) Start the engine, and turn Subaru Select Monitor or
OBD-II general scan tool switch to ON.
4) Warm-up the engine until engine coolant temperature is
above 70°C (160°F), and keep the engine speed at 2,000
rpm to 3,000 rpm for two minutes.
OBD0225
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F16

F16: Rear oxygen sensor output signal is indicated.
: Is the indicated data fluctuate?
: Go to step 5.
: Go to next.
: Is the indicated data fixed at 0.3±0.1 V?
: Go to step 4.
: Replace rear oxygen sensor.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

OBD0240
P: DTC P0170
—FUEL TRIM MALFUNCTION (FUEL)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Erroneous idling

Engine stalls.

Poor driving performance
1.Check exhaust system.
2.Check air intake system.
3.Check fuel pressure.
4.Check engine coolant temperature sensor.

5.Check mass air flow sensor.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODE. [T3D0] and [T3E0].>




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

4CHECK ENGINE COOLANT TEMPERATURE
SENSOR.
< REF. TO“F: DTC P0115 [T11F0].”>
1) Turn ignition switch to OFF.
OBD0145A
2) Connect the Subaru Select Monitor or the OBD-II gen-
eral scan tool to data link connector.
3) Start the engine and warm-up completely.
OBD0176
OBD0177
4) Read data on Subaru Select Monitor or the OBD-II gen-
eral scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F05 or F06

F05: Water temperature is indicated in“°F”.

F06: Water temperature is indicated in“°C”.
: Is temperature indicated on Subaru Select
Monitor (F05) greater than 140°F?
Is temperature indicated on Subaru Select
Monitor (F06) greater than 60°C?
: Go to step 5.
: Replace engine coolant temperature sensor.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
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11. Diagnostics Chart with Trouble Code

OBD0145A
5
CHECK MASS AIR FLOW SENSOR.
1) Turn ignition switch to OFF.
2) Connect the Subaru Select Monitor or the OBD-II gen-
eral scan tool to data link connector.
3) Start the engine and warm-up engine until coolant tem-
perature is greater than 60°C (140°F).
OBD0616
4) Read data on Subaru Select Monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F47

F47: Mass air flow is shown on display.
: Is the voltage within the specifications
shown in the following table?
Engine speed Specified value
Idling 1.9—3.6 (g/sec)
2,500 rpm 7.0—14.8 (g/sec)
: Replace mass air flow sensor.
: Contact with SOA service.
Note: Inspection by DTM is required.
Probable cause: Deterioration of plural parts

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
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11. Diagnostics Chart with Trouble Code

OBD0331
AE: DTC P0441
—EVAPORATIVE EMISSION CONTROL
SYSTEM INCORRECT PURGE FLOW
(CPC
—F)—
DESCRIPTION:

The evaporative emission control system is employed to
prevent evaporative fuel from being discharged into ambi-
ent atmosphere. This system includes a canister, purge
control solenoid valve, fuel cut valve, their connecting lines,
etc.

Gasoline vapor evaporated from the fuel tank is intro-
duced into the canister located in the engine compartment
through the evaporation line, and is absorbed on activated
carbon in it. A fuel cut valve is also incorporated on the tank
fuel line.

The purge control solenoid valve is controlled by the
ECM and provides optimal purge control according to the
engine coolant temperature, engine load and vehicle
speed.
OBD0332A
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11. Diagnostics Chart with Trouble Code

OBD0358
OBD0688A
AH: DTC P0505
—IDLE CONTROL SYSTEM MALFUNCTION
(ISC)—
DESCRIPTION:

Idle air control solenoid valve consists of an air cut valve,
duty control valve, intake air passage and a coolant pas-
sage.

Air cut valve contains a bimetallic substance which
responds to coolant temperature, and a duty control valve
which is operated by a signal sent from ECM.

When engine coolant temperature is low, air cut valve is
fully opened by the action of the bimetallic substance so
that the air flow required for low engine coolant tempera-
tures is maintained.

ECM controls duty control valve to bring the operating
engine speed as close to preset idle speed as possible.
DTC DETECTING CONDITION:

Immediately at fault recognition
TROUBLE SYMPTOM:

Erroneous idling

Engine stalls.

Engine breathing
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code