1997 SUBARU LEGACY ignition

10AI7
GROUP OF #3 AND #4 CYLINDERS
: Are there faults in #3 and #4 cylinders?
NOTE:

Check the following items.

Spark plugs

Fuel injectors

Ignition coil

If no abnormal is discovered, check for“D: IGNITION
CONTROL SYSTEM”of #3 and #4 cylinders side. 2-7 [T8D0].>
: Repair or replace faulty parts.
: Go to step10AI11.
10AI8
GROUP 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
: Repair or replace faulty parts.
: Go to step10AI11.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M0560A
10AJ1CHECK 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 step10AJ2.
: Go to next.
B2M0560A
: Connector & terminal
(B84) No. 3—Chassis ground:
Is the resistance less than 400 kΩ?
: Go to step10AJ3.
: Go to step10AJ4.
B2M1090
10AJ2
CHECK KNOCK SENSOR.
1) Disconnect connector from knock sensor.
2) Measure resistance between knock sensor connector
terminal and engine ground.
: Terminal
No. 2—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.
220
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M1090
10AJ3
CHECK KNOCK SENSOR.
1) Disconnect connector from knock sensor.
2) Measure resistance between knock sensor connector
terminal and engine ground.
: Terminal
No. 2—Engine ground:
Is the resistance less than 400 kΩ?
: Replace knock sensor.
: Repair ground 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
10AJ4
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.
221
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0718A
10AK1CHECK 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 ground short circuit in harness between
crankshaft position sensor and ECM connector.
NOTE:
The harness between both connectors are shielded.
Repair ground 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 step10AK2.
: 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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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0720A
10AM1CHECK HARNESS BETWEEN CAM-
SHAFT POSITION SENSOR AND ECM
CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from camshaft position sensor.
3) Measure resistance of harness between camshaft posi-
tion sensor connector and engine ground.
: Connector & terminal
(E15) 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 camshaft position sen-
sor and ECM connector

Poor contact in ECM connector

Poor contact in coupling connector (B20)
: Go to next.
OBD0720A
: Connector & terminal
(E15) No. 1—Engine ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in harness between
camshaft position sensor connector and ECM
connector.
NOTE:
The harness between both connectors are shielded.
Repair ground short circuit in harness together with shield.
: Go to next.
228
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.
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10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M1095
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.
: Does EGR valve operate at a throttle valve
opening of 5 to 10 degrees with visually
check?
: 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 step 8).
: Go to next step 8).
8) Turn ignition switch to OFF.
: 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.
: Clean EGR valve. And go toCONFIRMATION
OF ACTUAL DRIVING PATTERN.
CAUTION:
Do not use solvent when cleaning EGR valve
assembly, as it can damage diaphragm.
NOTE:

Remove and blow away the exhaust deposits. Make
sure the valve operates smoothly and the valve seat area
is completely cleaned.

Replace EGR valve as required.
235
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