1996 SUBARU LEGACY Brakes

tion cable)
(P6) No. 14—body/2Vorless (AEC communi-
cation cable)
B4M0740A
4. CHECK OUTPUT VOLTAGE OF ENGINE CONTROL
MODULE.
1) Turn ignition switch OFF.
2) Connect engine control module.
3) Connect ABS/TCS control module.
4) Turn ignition switch ON.
5) Measure voltage between engine control module con-
nector and body.
Connector & terminal / Specified voltage:
(B84) No. 74—body / 4—5.4 V (AET communi-
cation cable)
(B84) No. 73—body / 4—5.4 V (AEB communi-
cation cable)
(B84) No. 47—body / 4—5.4 V (AEC communi-
cation cable)
B4M0438A
5. CHECK BODY SHORT OF HARNESS.
1) Turn ignition switch OFF.
2) Disconnect engine control module.
3) Disconnect ABS/TCS control module.
4) Measure resistance between ABS/TCS control module
connector and body.
Connector & terminal / Specified resistance:
(P6) No. 12—body/1MΩor more (AET commu-
nication cable)
(P6) No. 5—body/1MΩor more (AEB communi-
cation cable)
(P6) No. 14—body/1MΩor more (AEC commu-
nication cable)
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8. Diagnostics Chart with Trouble Code

B4M0728A
6. CHECK OPEN CIRCUIT OF HARNESS.
1) Turn ignition switch OFF.
2) Disconnect engine control module.
3) Disconnect ABS/TCS control module.
4) Measure resistance between ABS/TCS control module
connector and engine control module connector.
(P6) No. 12—(B84) No. 74 / 1Ωor less (AET commu-
nication
cable)
(P6) No. 5—(B84) No. 73 / 1Ωor less (AEB commu-
nication cable)
(P6) No. 14—(B84) No. 47 / 1Ωor less (AEC com-
munication
cable)
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8. Diagnostics Chart with Trouble Code

I: TROUBLE CODE 51
—FAULTY VALVE RELAY—
DIAGNOSIS:

Faulty valve relay

Faulty harness/connector

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS does not operate.

TCS does not operate.
1. Check resistance of valve relay.
OK
Not OK
Replace valve relay.
2. Check contact point of valve relay.
OK
Not OK
Replace valve relay.
3. Check short circuit of valve relay.
OK
Not OK
Replace valve relay.
4. Check input voltage of valve relay.
OK
Not OK
Repair harness/connector.
5. Check ground circuit of valve relay.
OK
Not OK
Repair harness/connector.
6. Check harness between ABS/TCS control
module and valve relay.
OK
Not OK
Repair harness/connector.
7. Check resistance of valve relay to ABS/TCS
control module side.
OK
Not OK
Repair harness/connector.
8. Check body short of harness.
OK
Not OK
Repair harness.
Replace ABS/TCS control module.








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8. Diagnostics Chart with Trouble Code

B4M0440
B4M0441
1. CHECK RESISTANCE OF VALVE RELAY.
1) Turn ignition switch OFF.
2) Remove valve relay.
3) Measure resistance between valve relay terminals.
Terminal / Specified resistance:
No. A—B / 90±10Ω
B4M0442
2. CHECK CONTACT POINT OF VALVE RELAY.
1) Turn ignition switch OFF.
2) Remove valve relay.
3) Attach circuit tester probes to terminals as shown in
figure.
4) Measure resistance between respective terminals.
Terminal / Specified resistance:
No. C—E/1Ωor less (When 12 volts applied.)
No. C—E/1MΩor more
(When no voltage is applied.)
No. C—F/1MΩor more
(When 12 volts applied.)
No. C—F/1Ωor less
(When no voltage is applied.)
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8. Diagnostics Chart with Trouble Code

B4M0443
3. CHECK SHORT CIRCUIT OF VALVE RELAY.
1) Turn ignition switch OFF.
2) Remove valve relay.
3) Measure resistance between valve relay terminals.
Terminal / Specified resistance:
No. B—F/1MΩor more
B4M0444A
4. CHECK INPUT VOLTAGE OF VALVE RELAY.
1) Turn ignition switch OFF.
2) Disconnect valve relay.
3) Measure voltage between valve relay connector and
body.
Connector & terminal / Specified voltage:
(F11) No. 1—body/0V
(F11) No. 3—body / 10—13 V
4) Turn ignition switch ON.
5) Measure voltage between valve relay connector and
body.
Connector & terminal / Specified voltage:
(F11) No. 1—body / 10—13 V
(F11) No. 3—body / 10—13 V
B4M0445A
5. CHECK GROUND CIRCUIT OF VALVE RELAY.
1) Turn ignition switch OFF.
2) Disconnect valve relay.
3) Disconnect ABS/TCS control module.
4) Measure resistance between valve relay connector and
body.
Connector & terminal / Specified resistance:
(F11) No. 6—body / 1Ωor less
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8. Diagnostics Chart with Trouble Code

B4M0446A
6. CHECK HARNESS BETWEEN ABS/TCS CONTROL
MODULE AND VALVE RELAY.
1) Turn ignition switch OFF.
2) Disconnect valve relay.
3) Disconnect ABS/TCS control module.
4) Measure resistance between ABS/TCS control module
connector and body.
Connector & terminal / Specified resistance:
(P6) No. 6—body/1MΩor more
5) Connect valve relay.
6) Measure resistance between ABS/TCS control module
connector and body.
Connector & terminal / Specified resistance:
(P6) No. 6—body / 1Ωor less
B4M0447A
7. CHECK RESISTANCE OF VALVE RELAY TO ABS/
TCS CONTROL MODULE SIDE.
1) Turn ignition switch OFF.
2) Connect valve relay.
3) Disconnect ABS/TCS control module.
4) Measure resistance between ABS/TCS control module
connector terminals.
Connector & terminal / Specified resistance:
(P5) No. 1—(P6) No. 1 / 90±10Ω
B4M0729A
8. CHECK BODY SHORT OF HARNESS.
1) Turn ignition switch OFF.
2) Connect valve relay.
3) Disconnect ABS/TCS control module.
4) Turn ignition switch ON.
5) Measure voltage between ABS/TCS control module
connector and body.
Connector & terminal / Specified voltage:
(P6) No. 1—body / 10—13 V
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8. Diagnostics Chart with Trouble Code

J: TROUBLE CODE 52
—FAULTY MOTOR, MOTOR SENSOR AND/
OR MOTOR RELAY—
DIAGNOSIS:

Faulty motor relay

Faulty motor

Faulty motor sensor

Faulty harness/connector

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS does not operate.

TCS does not operate.
1. Check resistance of motor relay.
OK
Not OK
Replace motor relay.
2. Check input voltage of motor relay.
OK
Not OK
Repair harness/connector.
3. Check body short of harness.
OK
Not OK
Repair harness.
4. Check harness between ABS/TCS control
module and motor relay.
OK
Not OK
Repair harness/connector.
5. Check motor operation.
OK
Not OK
Go to step 10.
6. Check resistance of motor sensor.
OK
Not OK
Replace hydraulic unit.
7. Check body short of motor sensor.
OK
Not OK
Replace hydraulic unit.
8. Check harness between ABS/TCS control
module and motor sensor.
OK
Not OK
Repair harness/connector.
9. Check body short of motor sensor harness.
OK
Not OK
Repair harness.
Replace ABS/TCS control module.









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8. Diagnostics Chart with Trouble Code

10. Check contact point of motor relay.
OK
Replace motor relay.
11. Check harness between motor and motor
relay.
OK
Repair harness/connector.
12. Check body short of motor harness.
OK
Repair harness.
13. Check ground circuit of motor.
OK
Repair harness/connector.
Replace hydraulic unit.
B4M0741




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8. Diagnostics Chart with Trouble Code