SUBARU LEGACY 1996 Service Repair Manual

: Connector & terminal

With cruise control
(B107) No. 2 (+)—Chassis ground ():

Without cruise control
(B106) No. 2 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Replace starter interlock relay.
: Go to next step 3).
B2M0518A
3) Turn ignition switch to OFF.
4) Measure resistance between clutch switch connector
terminals while depressing the clutch pedal.
: Connector & terminal

With cruise control
(B107) No. 1—No. 2:

Without cruise control
(B106) No. 1—No. 2:
Is the resistance less than 10Ω?
: Repair harness between starter motor and ignition
switch connector.
: Replace clutch switch.
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8. Diagnostics for Engine Starting Failure

C: CONTROL MODULE POWER SUPPLY AND
GROUND LINE
8C1Check main relay.
8C2Check power supply circuit of ECM.
8C3Check ground circuit of ECM.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.
<Ref. to 2-7 [T3D0] and [T3E0].>
WIRING DIAGRAM:

LHD Model
B2M0519


94
2-7ON-BOARD DIAGNOSTICS II SYSTEM
8. Diagnostics for Engine Starting Failure

WIRING DIAGRAM:

RHD Model
B2M0782
95
2-7ON-BOARD DIAGNOSTICS II SYSTEM
8. Diagnostics for Engine Starting Failure

G2M0444
8C1
CHECK MAIN RELAY.
1) Turn the ignition switch to OFF.
2) Remove main relay.
3) Connect battery to main relay terminals No. 1 and No.
2.
4) Measure resistance between main relay terminals.
: Terminals
No. 3—No. 5:
Is the resistance less than 10Ω?
: Go to next.
: Replace main relay.
: Terminals
No. 4—No. 6:
Is the resistance less than 10Ω?
: Go to step8C2.
: Replace main relay.
B2M0520A
8C2CHECK POWER SUPPLY CIRCUIT OF
ECM.
1) Install main relay.
2) Disconnect connectors from ECM.
3) Turn ignition switch to ON.
4) Measure power supply voltage between ECM connec-
tor terminals.
: Connector & terminal
(B84) No. 1 (+)—No. 19 ():
Is the voltage more than 10 V?
: Go to next.
: Repair harness of power supply circuit.
: Connector & terminal
(B84) No. 2 (+)—No. 19 ():
Is the voltage more than 10 V?
: Go to next.
: Repair harness of power supply circuit.
: Connector & terminal
(B84) No. 39 (+)—No. 19 ():
Is the voltage more than 10 V?
: Go to step8C3.
: Repair harness of power supply circuit.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
8. Diagnostics for Engine Starting Failure

B2M0521A
8C3
CHECK GROUND CIRCUIT OF ECM.
1) Turn ignition switch to OFF.
2) Measure resistance of harness connector between
ECM and chassis ground.
: Connector & terminal
(B84) No. 17—Chassis ground:
Is the resistance less than 5Ω?
: Go to next.
: Repair harness between ECM connector and
engine grounding terminal.
: Connector & terminal
(B84) No. 18—Chassis ground:
Is the resistance less than 5Ω?
: Go to next.
: Repair harness between ECM connector and
engine grounding terminal.
: Connector & terminal
(B84) No. 19—Chassis ground:
Is the resistance less than 5Ω?
: Go to next.
: Repair harness between ECM connector and
engine grounding terminal.
: Connector & terminal
(B84) No. 20—Chassis ground:
Is the resistance less than 5Ω?
: Go to next.
: Repair harness between ECM connector and
engine grounding terminal.
: Connector & terminal
(B84) No. 42—Chassis ground:
Is the resistance less than 5Ω?
: Go to next.
: Repair harness between ECM connector and
engine grounding terminal.
: Connector & terminal
(B84) No. 46—Chassis ground:
Is the resistance less than 5Ω?
: Go to next.
: Repair harness between ECM connector and
engine grounding terminal.
: Connector & terminal
(B84) No. 69—Chassis ground:
Is the resistance less than 5Ω?
: Go to next.
: Repair harness between ECM connector and
engine grounding terminal.
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8. Diagnostics for Engine Starting Failure

: Connector & terminal
(B84) No. 94—Chassis ground:
Is the resistance less than 5Ω?
: Go to next.
: Repair harness between ECM connector and
engine grounding terminal.
: Connector & terminal
(B84) No. 95—Chassis ground:
Is the resistance less than 5Ω?
: Check ignition control system. <Ref. to 2-7
[T8D0].>
: Repair harness between ECM connector and
engine grounding terminal.
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8. Diagnostics for Engine Starting Failure

D: IGNITION CONTROL SYSTEM
8D1Check ignition system for sparks.
8D2Check power supply circuit for ignition coil.
8D3Check ignition coil.
8D4Check harness between ignitor and ignition
coil connector.
8D5Check input signal for ignitor.
8D6Check harness of ignitor ground circuit.
8D7Check harness between ECM and ignitor
connector.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.
<Ref. to 2-7 [T3D0] and [T3E0].>
WIRING DIAGRAM:
B2M0522






99
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8. Diagnostics for Engine Starting Failure

OBD0727A
B2M0644A
8D1
CHECK IGNITION SYSTEM FOR SPARKS.
1) Remove plug cord cap from each spark plug.
2) Install new spark plug on plug cord cap.
CAUTION:
Do not remove spark plug from engine.
3) Contact spark plug’s thread portion on engine.
4) While opening throttle valve fully, crank engine to check
that spark occurs at each cylinder.
: Does spark occur at each cylinder?
: Check fuel pump system. <Ref. to 2-7 [T8E0].>
: Go to step8D2.
OBD0123A
8D2CHECK POWER SUPPLY CIRCUIT FOR
IGNITION COIL.
1) Turn ignition switch to OFF.
2) Disconnect connector from ignition coil.
3) Turn ignition switch to ON.
4) Measure power supply voltage between ignition coil
connector and engine ground.
: Connector & terminal
(E12) No. 2 (+)—Engine ground ():
Is the voltage more than 10 V?
: Go to step8D3.
: Repair harness between ignition coil and ignition
switch connector.
OBD0124
8D3
CHECK IGNITION COIL.
1) Measure resistance between ignition coil terminals to
check primary coil.
: Terminals
No. 2—No. 1:
Is the resistance between 0.4 and 1.0Ω?
: Go to next.
: Replace ignition coil.
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8. Diagnostics for Engine Starting Failure

: Terminals
No. 2—No. 3:
Is the resistance between 0.4 and 1.0Ω?
: Replace ignition coil.
: Go to next step 2).
OBD0125A
2) Measure resistance between spark plug cord contact
portions to check secondary coil.
: Terminals
#1—#2:
Is the resistance between 18 and 24Ω?
: Go to next.
: Replace ignition coil.
: Terminals
#3—#4:
Is the resistance between 18 and 24Ω?
: Go to step8D4.
: Replace ignition coil.
OBD0126A
8D4CHECK HARNESS BETWEEN IGNITOR
AND IGNITION COIL CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from ignitor.
3) Measure resistance of harness connector between igni-
tion coil and ignitor.
: Connector & terminal
(B13) No. 5—(E12) No. 1:
Is the resistance less than 1Ω?
: Go to next.
: Go to next.
: Connector & terminal
(B13) No. 6—(E12) No. 3:
Is the resistance less than 1Ω?
: Go to step8D5.
: Go to next.
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8. Diagnostics for Engine Starting Failure

: Is there poor contact in coupling connector
(B22)?
: Repair poor contact in coupling connector.
: Repair harness between ignition coil and ignitor
connector.
OBD0728
B2M0224A
8D5
CHECK INPUT SIGNAL FOR IGNITOR.
Check if voltage varies synchronously with engine speed
when cranking, while monitoring voltage between ignitor
connector and engine ground.
: Connector & terminal:
(B13) No. 1 (+)—Engine ground ():
Is the voltage more than 10 V?
: Go to next.
: Replace ignitor.
: Connector & terminal:
(B13) No. 2 (+)—Engine ground ():
Is the voltage more than 10 V?
: Go to step8D6.
: Replace ignitor.
OBD0128A
8D6CHECK HARNESS OF IGNITOR GROUND
CIRCUIT.
1) Turn ignition switch to OFF.
2) Measure resistance between ignitor and engine ground.
: Connector & terminal
(B13) No. 3—Engine ground:
Is the resistance less than 5Ω?
: Go to step8D7.
: Repair harness between ignitor connector and
engine grounding terminal.
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8. Diagnostics for Engine Starting Failure