engine SUBARU LEGACY 1996 Service Repair Manual

: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Replace ECM.
OBD0713A
10V3CHECK HARNESS BETWEEN FUEL
INJECTOR AND ECM CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from fuel injector on faulty cylin-
ders.
3) Measure resistance between ECM connector and
engine ground on faulty cylinders.
: Connector & terminal
#1 (E5) No. 1—Engine ground:
#2 (E16) No. 1—Engine ground:
#3 (E6) No. 1—Engine ground:
#4 (E17) No. 1—Engine ground:
Is the resistance less than 10Ω?
: Repair short circuit in harness between fuel injec-
tor and ECM connector.
: Go to next step 4).
B2M0557A
4) Measure resistance of harness connector between
ECM connector and fuel injector on faulty cylinders.
: Connector & terminal
#1 (B84) No. 96—(E5) No. 1:
#2 (B84) No. 70—(E16) No. 1:
#3 (B84) No. 44—(E6) No. 1:
#4 (B84) No. 16—(E17) No. 1:
Is the resistance less than 1Ω?
: Go to step10V4.
: Repair open circuit in harness between ECM and
fuel injector connector.
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10. Diagnostics Chart with Trouble Code

G2M0464
10V4
CHECK FUEL INJECTOR.
Measure resistance between fuel injector terminals on
faulty cylinder.
: Terminals
No. 1—No. 2:
Is the resistance between 5 and 20Ω?
: Replace faulty fuel injector.
: Go to step10V5.
OBD0715A
10V5
CHECK POWER SUPPLY LINE.
1) Turn ignition switch to ON.
2) Measure voltage between fuel injector and engine
ground on faulty cylinders.
: Connector & terminal
#1 (E5) No. 2 (+)—Engine ground ():
#2 (E16) No. 2 (+)—Engine ground ():
#3 (E6) No. 2 (+)—Engine ground ():
#4 (E17) No. 2 (+)—Engine ground ():
Is the voltage more than 10 V?
: Repair poor contact in all connectors in fuel injec-
tor circuit.
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between main relay and fuel
injector connector on faulty cylinders

Poor contact in main relay connector

Poor contact in fuel injector connector on faulty cylinders
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10. Diagnostics Chart with Trouble Code

OBD0277
W: DTC P0301
—CYLINDER 1 MISFIRE DETECTED
(MIS
—1)—
OBD0278
X: DTC P0302
—CYLINDER 2 MISFIRE DETECTED
(MIS
—2)—
OBD0279
Y: DTC P0303
—CYLINDER 3 MISFIRE DETECTED
(MIS
—3)—
OBD0280
Z: DTC P0304
—CYLINDER 4 MISFIRE DETECTED
(MIS
—4)—
DTC DETECTING CONDITION:

Two consecutive trips with fault

Immediately at fault recognition (A misfire which could
damage catalyst occurs.)
TROUBLE SYMPTOM:

Engine stalls.

Erroneous idling

Rough driving
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10. Diagnostics Chart with Trouble Code

OBD0145A
10Z2CONNECT SUBARU SELECT MONITOR
AND READ DATA.
1) Turn ignition switch to OFF.
2) Connect Subaru Select Monitor to the data link connec-
tor.
3) Turn ignition switch to ON and turn Subaru Select Moni-
tor switch to ON.
B2M0759
4) Read data on Subaru Select Monitor.
Designate mode use function key.
Function mode: F42
NOTE:
F42: Maximum and minimum EGR system pressure value
are indicated at the same time.
5) Print out the displayed data on paper.
G3M0152
6) Clear memory on Subaru Select Monitor.
Designate mode use function key.
Press [F], [C], [0], [ENT] in that order.
OBD0008C
7) Start engine, and drive the vehicle more than 10 min-
utes.
: Is the MIL coming on or blinking?
: Go to step10Z3.
: Go to next.
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10. Diagnostics Chart with Trouble Code

: Has the vehicle been run empty of fuel?
: Finish diagnostics operation, if the engine has no
abnormality.
: Go to next.
: Was the cause of misfire diagnosed when
the engine is running?
NOTE:
Ex. Remove spark plug cord, etc.
: Finish diagnostics operation, if the engine has no
abnormality.
: Repair connector.
NOTE:
In this case, repair the following:

Poor contact in ignitor connector

Poor contact in ignition coil connector

Poor contact in fuel injector connector on faulty cylinders

Poor contact in ECM connector

Poor contact in coupling connector (B22)
10Z3
CHECK AIR INTAKE SYSTEM.
: Is there a fault in air intake system?
NOTE:
Check the following items:

Are there air leaks or air suction caused by loose or dis-
located nuts and bolts?

Are there cracks or any disconnection of hoses?
: Repair air intake system.
: Go to step10Z4.
OBD0145A
10Z4
CHECK MISFIRE SYMPTOM.
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) Turn ignition switch to ON, and turn Subaru Select
Monitor or OBD-II general scan tool switch to ON.
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10. Diagnostics Chart with Trouble Code

3GROUP OF #3 AND #4 CYLINDERS
: Are there faults in #3 and #4 cylinders?
NOTE:
Check the following items.

Spark plugs

Fuel injectors

Ignition coil
: Go to next.
: Go to DTC P0170, 2-7 [T10P3], [T10P4] and
[T10P5].
NOTE:
If no abnormal is discovered, check for“8. F: IGNITION
SYSTEM”of #3 and #4 cylinders side.

4GROUP OF #1 AND #3 CYLINDERS
: Are there faults in #1 and #3 cylinders?
NOTE:
Check the following items.

Spark plugs

Fuel injectors

Skipping timing belt teeth
: Go to next.
: Go to DTC P0170, 2-7 [T10P3], [T10P4] and
[T10P5].

5GROUP OF #2 AND #4 CYLINDERS
: Are there faults in #2 and #4 cylinders?
NOTE:
Check the following items.

Spark plugs

Fuel injectors

Skipping timing belt teeth
: Go to next.
: Go to DTC P0170, 2-7 [T10P3], [T10P4] and
[T10P5].

6THE CYLINDER AT RANDOM
: Is the engine idle rough?
: Go to next.
: Go to DTC P0170, 2-7 [T10P3], [T10P4] and
[T10P5].
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10. Diagnostics Chart with Trouble Code

B2M0560A
10AA1CHECK HARNESS BETWEEN KNOCK
SENSOR AND ECM CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from ECM.
3) Measure resistance between ECM harness connector
and chassis ground.
: Connector & terminal
(B84) No. 3—Chassis ground:
Is the resistance more than 700 kΩ?
: Go to step10AA2.
: Go to next.
B2M0560A
: Connector & terminal
(B84) No. 3—Chassis ground:
Is the resistance less than 400 kΩ?
: Go to step10AA3.
: Go to step10AA4.
B2M0244A
10AA2
CHECK KNOCK SENSOR.
1) Disconnect connector from knock sensor.
2) Measure resistance between knock sensor connector
terminal and engine ground.
: Terminal
No. 1—Engine ground:
Is the resistance more than 700 kΩ?
: Go to next.
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between knock sensor and ECM
connector

Poor contact in knock sensor connector

Poor contact in coupling connector (B21)
: Is the knock sensor installation bolt tight-
ened securely?
: Replace knock sensor.
: Tighten knock sensor installation bolt securely.
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10. Diagnostics Chart with Trouble Code

B2M0244A
10AA3
CHECK KNOCK SENSOR.
1) Disconnect connector from knock sensor.
2) Measure resistance between knock sensor connector
terminal and engine ground.
: Terminal
No. 1—Engine ground:
Is the resistance less than 400 kΩ?
: Replace knock sensor.
: Repair short circuit in harness between knock
sensor connector and ECM connector.
NOTE:
The harness between both connectors is shielded. Repair
short circuit of harness together with shield.
B2M0561A
10AA4
CHECK INPUT SIGNAL FOR ECM.
1) Connect connectors to ECM and knock sensor.
2) Turn ignition switch to ON.
3) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 3 (+)—Chassis ground ():
Is the voltage more than 2 V?
: 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 knock sensor connector

Poor contact in ECM connector

Poor contact in coupling connector (B21)
: Repair poor contact in ECM connector.
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10. Diagnostics Chart with Trouble Code

OBD0292
AB: DTC P0335
—CRANKSHAFT POSITION SENSOR
CIRCUIT MALFUNCTION (CRANK)—
DTC DETECTING CONDITION:

Immediately at fault recognition
TROUBLE SYMPTOM:

Engine stalls.

Failure of engine to start
10AB1Check harness between crankshaft position
sensor and ECM connector.
10AB2Check crankshaft position sensor.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

WIRING DIAGRAM:
B2M0529

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10. Diagnostics Chart with Trouble Code

OBD0718A
10AB1CHECK HARNESS BETWEEN CRANK-
SHAFT POSITION SENSOR AND ECM
CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from crankshaft position sensor.
3) Measure resistance of harness between crankshaft
position sensor connector and engine ground.
: Connector & terminal
(E10) No. 1—Engine ground:
Is the resistance more than 100 kΩ?
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between crankshaft position
sensor and ECM connector

Poor contact in ECM connector

Poor contact in coupling connector (B20)
: Go to next.
OBD0718A
: Connector & terminal
(E10) No. 1—Engine ground:
Is the resistance less than 10Ω?
: Repair short circuit in harness between crankshaft
position sensor and ECM connector.
NOTE:
The harness between both connectors are shielded.
Repair short circuit in harness together with shield.
: Go to next.
OBD0719A
: Connector & terminal
(E10) No. 2—Engine ground:
Is the resistance less than 5Ω?
: Go to step10AB2.
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between crankshaft position
sensor and ECM connector

Poor contact in ECM connector

Poor contact in coupling connector (B20)
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10. Diagnostics Chart with Trouble Code