SUBARU LEGACY 1996 Service Repair Manual

WIRING DIAGRAM:

RHD Model
B2M0799
OBD0736A
10BQ1
CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to OFF.
2) Connect test mode connector at the lower portion of
instrument panel (on the driver’s side), to the side of the
center console box.
3) Turn ignition switch to ON.
B2M0608A
4) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 74 (+)—Chassis ground:
Is the voltage more than 10 V?
: Go to step10BQ5.
: Go to step10BQ2.
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10. Diagnostics Chart with Trouble Code

10BQ2
CHECK POWER SUPPLY FOR RELAYS.
Turn ignition switch to OFF.
: Is the fuse in power supply circuit broken?
: Replace the fuse.
: Go to step10BQ3.
OBD0535
10BQ3CHECK MAIN FAN RELAY 1, SUB FAN
RELAY 1 AND MAIN FAN RELAY.
1) Remove main fan relay 1. (With A/C models only)
2) Measure resistance between main fan relay 1 termi-
nals.
: Terminal
No. 1—No. 3:
Is the resistance between 87 and 107Ω?
: Go to next step 3).
: Replace main fan relay 1.
OBD0536
3) Remove sub fan relay 1. (With A/C models only)
Remove main fan relay. (Without A/C models only)
4) Measure resistance between sub fan relay 1 or main
fan relay terminals.
: Terminal
No. 1—No. 3:
Is the resistance between 83 and 117Ω?
: Go to step10BQ4.
: Replace sub fan relay 1.
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10. Diagnostics Chart with Trouble Code

B2M0609A
10BQ4CHECK OPEN CIRCUIT IN RADIATOR
FAN RELAY 1 CONTROL CIRCUIT.
1) Disconnect connector from ECM.
2) Disconnect connector from sub fan relay 1 or main fan
relay.
3) Measure resistance of harness between ECM and main
fan relay 1 connector.
NOTE:
With A/C models only.
: Connector & terminal
(B84) No. 74—(F28) No. 3:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between ECM and
main fan relay 1 connector.
: Is there poor contact in ECM or main fan
relay 1 connector?
: Repair poor contact in ECM or main fan relay 1
connector.
: Go to next step 4).
B2M0610A
4) Measure resistance of harness between ECM and sub
fan relay 1 (with A/C models) or main fan relay (without A/C
models) connector.
: Connector & terminal
(B84) No. 74—(F40) No. 4:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between ECM and
sub fan relay 1 (with A/C models) or main fan relay
(without A/C models) connector.
: Is there poor contact in ECM or sub fan
relay 1 (with A/C models) or main fan relay
(without A/C models) connector?
: Repair poor contact in ECM or sub fan relay 1 (with
A/C models) or main fan relay (without A/C mod-
els) connector.
: Go to next step 5) (with A/C models) or step 6)
(without A/C models).
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10. Diagnostics Chart with Trouble Code

OBD0686A
5) Measure resistance of harness between main fan relay
1 and ignition switch connector.
NOTE:
With A/C models only.
: Connector & terminal
(F28) No. 1—(F72) No. 5:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between main fan
relay 1 and ignition switch connector.
: Is there poor contact in main fan relay 1 or
ignition switch connector?
: Repair main fan relay 1 or ignition switch connec-
tor.
: Go to next step 6).
OBD0687A
6) Measure resistance of harness between sub fan relay
1 (with A/C models) or main fan relay (without A/C models)
and ignition switch connector.
: Connector & terminal
(B52) No. 4—(F72) No. 2:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between sub fan
relay 1 (with A/C models) or main fan relay (with-
out A/C models) and ignition switch connector.
: Is there poor contact in sub fan relay 1 (with
A/C models) or main fan relay (without A/C
models) or ignition switch connector?
: Repair poor contact in sub fan relay 1 (with A/C
models) or main fan relay (without A/C models) or
ignition switch connector.
: Replace ECM.
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10. Diagnostics Chart with Trouble Code

B2M0611A
10BQ5CHECK SHORT CIRCUIT IN RADIATOR
FAN RELAY 1 CONTROL CIRCUIT.
1) Turn ignition switch to OFF.
2) Remove main fan relay 1 and sub fan relay 1. (with A/C
models)
Remove main fan relay. (without A/C models)
3) Disconnect test mode connector.
4) Turn ignition switch to ON.
5) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 74 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Repair short circuit in radiator fan relay 1 control
circuit and replace ECM.
: Go to next.
: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Replace ECM.
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10. Diagnostics Chart with Trouble Code

OBD0538
BR: DTC P1502
—RADIATOR FAN FUNCTION PROBLEM
(FAN
—F)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Occurrence of noise

Overheating
10BR1Check any other DTC (beside DTC P1502) on
display.
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.
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10. Diagnostics Chart with Trouble Code

WIRING DIAGRAM:

LHD Model
B2M0612
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10. Diagnostics Chart with Trouble Code

WIRING DIAGRAM:

RHD Model
B2M0800
10BR1CHECK 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, 2-7 [T1000]”.
: Check engine cooling system. [K100].>
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10. Diagnostics Chart with Trouble Code

OBD0501
BS: DTC P1700
—THROTTLE POSITION SENSOR CIRCUIT
MALFUNCTION FOR AUTOMATIC
TRANSMISSION (ATTH)—
DTC DETECTING CONDITION:

Two consecutive trips 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”
10BS1Check DTC P1700 on display.
Check throttle position sensor circuit.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

WIRING DIAGRAM:
B2M0613
10BS1
CHECK DTC P1700 ON DISPLAY.
: Does the Subaru select monitor or OBD-II
general scan tool indicate DTC P1700?
: Check throttle position sensor circuit.
NOTE:
For the diagnostic procedure on throttle position sensor
circuit, refer to 3-2 [T7K0].

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10. Diagnostics Chart with Trouble Code

B2M0669
BT: DTC P1701
—CRUISE CONTROL SET SIGNAL CIRCUIT
MALFUNCTION FOR AUTOMATIC
TRANSMISSION (ATCRS)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
10BT1Check harness between TCM and CCM
connector.
10BT2Check input signal for TCM.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

WIRING DIAGRAM:
OBD0512

362
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10. Diagnostics Chart with Trouble Code