SUBARU LEGACY 1995 Service Repair Manual

OBD0489
BG: DTC P1103
—ENGINE TORQUE CONTROL SIGNAL
CIRCUIT MALFUNCTION (TRQ)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Excessive shift shock
1.Check input signal for ECM.
2.Check harness connector between ECM and
TCM.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES. <Ref. to
[T3D0] and [T3E0].>
WIRING DIAGRAM:
OBD0490

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11. Diagnostics Chart with Trouble Code

OBD0491A
1
CHECK INPUT SIGNAL FOR ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and body.
: Connector & terminal
(B84) No. 49—Body / 4.5V, or more
: Go to next.
: Go to step 2.
: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Replace ECM with a new one.
OBD0492B
2CHECK HARNESS CONNECTOR BETWEEN
ECM AND TCM.
1) Turn ignition switch to OFF.
2) Disconnect connectors from ECM and TCM.
3) Measure resistance of harness connector between
ECM and TCM.
: Connector & terminal
(B84) No. 49—(B55) No. 16 / 10Ω, or less
: Go to next step.
: Repair open circuit of harness between ECM con-
nector and TCM connector.
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11. Diagnostics Chart with Trouble Code

OBD0493A
4) Measure resistance of harness connector between
ECM and body.
: Connector & terminal
(B84) No. 49—Body / 1 MΩ, or more
: Go to next.
: Repair short circuit of harness between ECM con-
nector and TCM connector.
: Is there poor contact in TCM connector?
: Repair poor contact in TCM connector.
: Replace TCM with a new one.
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11. Diagnostics Chart with Trouble Code

OBD0494
BH: DTC P1104
—TCS SIGNAL CIRCUIT MALFUNCTION
(TCS)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

No operation TCS

TCS warning light remains illuminated.
1.Check if the vehicle is equipped with TCS.

2.Check output signal from ECM.
3.Check harness connector.
4.Check ECM connector.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES. <Ref. to
[T3D0] and [T3E0].>
WIRING DIAGRAM:
OBD0495


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11. Diagnostics Chart with Trouble Code

1CHECK IF THE VEHICLE IS EQUIPPED WITH
TCS.
: Is the vehicle equipped with TCS?
: Go to step 4.
: Go to step 2.
OBD0497A
2
CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM connector and body.
: Connector & terminal
(B84) No. 34—Body / 2 V, or more
: Repair poor contact in ECM connector.
: Go to step 3.
OBD0499A
3
CHECK HARNESS CONNECTOR.
1) Turn ignition switch to OFF.
2) Remove front passenger side seat.
3) Tear off the floor mat.
4) Disconnect connectors from ECM and TCS C/M.
5) Measure resistance between ECM harness connector
and body.
: Connector & terminal
(B84) No. 34—Body / 10Ω, or less
: Repair short circuit of harness between ECM con-
nector and TCS C/M connector.
: Go to next step.
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11. Diagnostics Chart with Trouble Code

OBD0498A
6) Measure resistance of harness connector between
ECM and TCS C/M.
: Connector & terminal
(B84) No. 34—(P6) No. 4 / 10Ω, or less
:
Open circuit of harness between ECM connec-
tor and TCS C/M connector

Poor contact in ECM connector

Poor contact in TCS C/M connector
Check above points and repair if necessary.
: Go to next step.
OBD0497A
7) Turn ignition switch to ON.
8) Measure voltage between ECM connector and body.
: Connector & terminal
(B84) No. 34—Body/2 V, or more
: Repair short circuit of harness between ECM and
TCS C/M connector.
: Repair poor contact in TCS C/M connector.
OBD0500A
4
CHECK ECM CONNECTOR.
1) Turn ignition switch to ON.
2) Measure voltage between ECM connector and body.
: Connector & terminal
(B84) No. 74—Body / 2 V, or more
: Repair open circuit of harness between ECM con-
nector and body.
: Repair poor contact in ECM connector.
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11. Diagnostics Chart with Trouble Code

OBD0527
BI: DTC P1500
—RADIATOR FAN RELAY 1 CIRCUIT
MALFUNCTION (FAN
—1)—
DESCRIPTION:

The engine cooling system consists of a down-flow
radiator which features high heat-dissipation performance,
an electric motor fan, an engine coolant pump, a
thermostat, and an engine coolant temperature sensor.

The ON-OFF control of the radiator fan is governed by
the ECM which receives signals sent from the engine cool-
ant temperature sensor. On models which are equipped
with an air conditioning system, the ECM receives signals
sent from the engine coolant temperature sensor, vehicle
speed sensor 2 and A/C switch. These signals simulta-
neously turn ON or OFF the radiator main fan and radiator
sub fan as well as setting them at“HI”or“LO”speed.
[Without A/C models]
Engine coolant temperature signal *1ECM output signal Operation of radiator fan
Radiator fan relay 1 Main
ON ON ON
OFF OFF OFF
*1 ON: Above 95°C (203°F), OFF: Below 89°C (192°F)
[With A/C models]
Engine coolant
temperature
signal *2A/C compressorVehicle speed
signal *3ECM output signal Operation of radiator fan
Radiator fan
relay 1Radiator fan
relay 2Main Sub
ONONON ON ON HI HI
OFF ON ON HI HI
OFFON ON ON HI HI
OFF ON OFF LO LO
OFFONON ON ON HI HI
OFF ON OFF LO LO
OFFON OFF OFF OFF OFF
OFF OFF OFF OFF OFF
*2 ON: Above 95°C (203°F), OFF: Below 89°C (192°F)
*3 ON: Above 20 km/h (12 MPH), OFF: Below 10 km/h (6 MPH)
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11. Diagnostics Chart with Trouble Code

DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Radiator fan does not operate properly.

Overheating
1.Check output signal from ECM.


2.Check power supply for relays.
3.Check main fan relay 1, sub fan relay 1 and
main fan relay.
4.Check harness connector.
5.Check harness connector.
6.Check monitor line.
Check radiator fan function problem. <Ref. to“BJ: DTC
P1502 [T11BJ0]”.>
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODE. <Ref. to
[T3D0] and [T3E0].>




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11. Diagnostics Chart with Trouble Code

WIRING DIAGRAM:

LHD model
OBD0528
WIRING DIAGRAM:

RHD model
B2M0460
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11. Diagnostics Chart with Trouble Code

OBD0736A
1
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.
OBD0674A
4) Measure voltage between ECM and body.
: Connector & terminal
(B84) No. 77—Body/10 V, or more and 1 V
or less at every 2 seconds
: Go to step 6.
: Go to next.
OBD0534A
: Connector & terminal
(B84) No. 88—Body/10 V, or more
: Go to step 5.
: Go to step 2.
2
CHECK POWER SUPPLY FOR RELAYS.
Turn ignition switch to OFF.
: Is the fuse in power supply circuit broken?
: Replace the fuse.
: Go to step 3.
OBD0535
3CHECK 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. 3/97±10Ω
: Go to next step.
: Replace main fan relay 1.
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11. Diagnostics Chart with Trouble Code