engine SUBARU LEGACY 1997 Service Repair Manual

OBD0145A
10CK1
CHECK DATA FOR CONTROL.
1) Turn ignition switch to OFF.
2) Connect Subaru Select Monitor or the OBD-II general
scan tool to data link connector.
3) Turn ignition switch ON and Subaru Select Monitor or
the OBD-II general scan tool switch ON.
4) Start engine.
5) Read data on Subaru Select Monitor or the OBD-II gen-
eral scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F20

F20: Display shows pressure signal value sent from the
pressure sensor.
B2M0755
: Is the value more than 133 kPa in function
mode F20?
: Replace pressure sensor.
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. Contact with SOA
service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple 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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10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M1132
CN: DTC P1421
—EXHAUST GAS RECIRCULATION CIRCUIT
HIGH INPUT—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
TROUBLE SYMPTOM:

Poor driving performance on low engine speed
WIRING DIAGRAM:
B2M1096
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

377
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

10CN1
CHECK ENGINE/TRANSMISSION TYPE.
: Is engine/transmission type 2200 cc/MT?
: Check AT/MT identification circuit. [T10DD0].>
: Go to step10CN2.
B2M0566A
10CN2
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 step10CN3.
: Go to next.
: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Replace ECM.
B2M0566A
10CN3CHECK HARNESS BETWEEN EGR
SOLENOID VALVE AND ECM CONNEC-
TOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from EGR solenoid valve.
3) Turn ignition switch to ON.
4) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 71 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Repair battery short circuit in harness between
ECM and EGR solenoid valve connector. After
repair, replace ECM.
: Go to next step 5).
378
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

NOTE:
If the vehicle, with the engine idling, is placed very close to
a wall or another vehicle, preventing normal cooling
function, the OBD system may detect malfunction.
10CU1CHECK ANY OTHER DTC (BESIDE DTC
P1502) ON DISPLAY.
: Is there any other DTC on display?
: Inspect the relevant DTC using“10. Diagnostics
Chart with Trouble Code”.
: Check engine cooling system. [K100].>
402
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M1140
CV: DTC P1507
—IDLE CONTROL SYSTEM MALFUNCTION
(FAIL-SAFE)—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
TROUBLE SYMPTOM:

Engine keeps running at higher revolution than specified
idling revolution.
WIRING DIAGRAM:
B2M1311
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

403
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

10CV1
CHECK DTC P0505 ON DISPLAY.
: Does the Subaru select monitor or OBD-II
general scan tool indicate DTC P0505?
: Inspect DTC P0505 using“10. Diagnostics Chart
with Trouble Code”.
NOTE:
In this case, it is not necessary to inspect DTC P1507.
: Go to step10CV2.
10CV2
CHECK AIR INTAKE SYSTEM.
1) Turn ignition switch to ON.
2) Start engine, and idle it.
: Is there a fault in air intake system?
NOTE:
Check the following items.

Loose installation of intake manifold, idle air control sole-
noid valve and throttle body

Cracks of intake manifold gasket, idle air control sole-
noid valve gasket and throttle body gasket

Loose connections and cracks of idle air control solenoid
valve by-pass hoses

Disconnections of vacuum hoses
: Repair air suction and leaks.
: Replace idle air control solenoid valve.
404
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10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0501
CY: DTC P1700
—THROTTLE POSITION SENSOR CIRCUIT
MALFUNCTION FOR AUTOMATIC
TRANSMISSION—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
TROUBLE SYMPTOM:

Shift point too high or too low; engine brake not effected
in“3”range; excessive shift shock; excessive tight corner
“braking”
WIRING DIAGRAM:
B2M0613
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

409
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10. Diagnostic Chart with Trouble Code for LHD Vehicles

: Connector & terminal
(B56) No. 3—(B94) No. 3:
Is the resistance less than 1Ω?
: Go to next step 4).
: Repair open circuit in harness between TCM and
CCM connector.
OBD0515A
4) Measure resistance of harness between TCM and
chassis ground.
: Connector & terminal
(B56) No. 3—Chassis ground:
Is the resistance less than 10Ω?
: Repair short circuit in harness between TCM and
CCM connector.
: Go to step10CZ2.
OBD0513A
10CZ2
CHECK INPUT SIGNAL FOR TCM.
1) Connect connector to TCM and CCM.
2) Lift-up the vehicle or set the vehicle on free rollers.
CAUTION:
On AWD models, raise all wheels off ground.
3) Start the engine.
4) Cruise control main switch to ON.
5) TCS OFF switch to ON. (with TCS models only)
6) Move selector lever to“D”and slowly increase vehicle
speed to 50 km/h (31 MPH).
7) Cruise control set switch to ON.
8) Measure voltage between TCM and chassis ground.
: Connector & terminal
(B56) No. 3 (+)—Chassis ground ():
Is the resistance less than 1 V?
: Go to next.
: Check cruise control set circuit. [T7A0].>
: Is there poor contact in TCM connector?
: Repair poor contact in TCM connector.
: Replace TCM.
412
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10. Diagnostic Chart with Trouble Code for LHD Vehicles

10DC1
CHECK TRANSMISSION TYPE.
: Is transmission type AT?
: Go to step10DC2.
: Check AT/MT identification circuit. [T10DD0].>
10DC2
CHECK DRIVING CONDITION.
1) Start and warm-up the engine until the radiator fan
makes one complete rotation.
2) Drive the vehicle.
: Is AT shift control functioning properly?
: Go to step10DC3.
: Replace TCM.
10DC3
CHECK ACCESSORY.
: Are car phone and/or CB installed on
vehicle?
: Repair grounding line of car phone or CB system.
: Replace TCM.
420
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10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M0618A
10DD1CHECK HARNESS BETWEEN ECM CON-
NECTOR AND ENGINE GROUNDING
TERMINAL.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 81 (+)—Chassis ground ():
Is the voltage more than 2 V?
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between ECM connector and
engine grounding terminal

Poor contact in engine grounding terminal

Poor contact in coupling connector (B22)
: Go to next.
: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Contact with SOA service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
422
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles