SUBARU LEGACY 1997 Service Repair Manual

5. CHECK SOURCES OF SIGNAL NOISE.
1) Check that the mobile phone, personal radio and other
wireless apparatus are correctly installed.
2) Check that the antenna and other possible noise
sources are distant enough from the sensor harness.
3) Check that the sealed wires of the front harness sensor
(in the engine room) are securely grounded.
4) Check that between ABS/TCS control module and the
rear sensor harness has the correct twist pitch.
Twist pitch:
25 mm (0.98 in) or less
6. CHECK HYDRAULIC UNIT OPERATIONS.
1) Operate the ABS sequence control and check that the
brake fluid pressure at the malfunctioning brake line
increases and decreases properly.
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8. Diagnostics Chart with Trouble Code

D: TROUBLE CODE 31, 33, 35, 37, 61 AND 62
—FAULTY INLET SOLENOID VALVE
CIRCUIT(S) AND TCS SOLENOID VALVE
CIRCUIT(S) IN HYDRAULIC UNIT—
DIAGNOSIS:

Faulty harness/connector

Faulty solenoid valve in hydraulic unit

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS does not operate.

TCS does not operate.

ABS sequence control does not operate.

TCS sequence control does not operate.

Air bleeding mode does not operate.
1. Check resistance of solenoid valve.
OK
Not OK
Replace hydraulic unit.
2. Check body short of solenoid valve.
OK
Not OK
Replace hydraulic unit.
3. Check body short of harness.
OK
Not OK
Repair harness.
4. Check harness between ABS/TCS control
module and hydraulic unit.
OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.




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8. Diagnostics Chart with Trouble Code

B4M0739
B4M0722A
1. CHECK RESISTANCE OF SOLENOID VALVE.
1) Turn ignition switch OFF.
2) Disconnect connector from hydraulic unit.
3) Measure resistance between hydraulic unit terminals.
TROUBLE CODE / Connector & terminal:
31 / (F15) No. 3—No. 9
33 / (F15) No. 4—No. 10
35 / (F15) No. 1—No. 10
37 / (F15) No. 2—No. 9
61 / (F15) No. 12—No. 9
62 / (F15) No. 11—No. 10
Specified resistance: approx. 6±1Ω
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8. Diagnostics Chart with Trouble Code

B4M0723A
2. CHECK BODY SHORT OF SOLENOID VALVE.
1) Turn ignition switch OFF.
2) Disconnect connector from hydraulic unit.
3) Measure resistance between hydraulic unit terminals.
TROUBLE CODE / Connector & terminal:
31 / (F15) No. 3—body
33 / (F15) No. 4—body
35 / (F15) No. 1—body
37 / (F15) No. 2—body
61 / (F15) No. 12—body
62 / (F15) No. 11—body
Specified resistance: 1 MΩor more
B4M0419A
3. CHECK BODY SHORT OF HARNESS.
1) Turn ignition switch OFF.
2) Disconnect connector from hydraulic unit.
3) Disconnect connector from ABS/TCS control module.
4) Measure resistance between ABS/TCS control module
connector terminals.
TROUBLE CODE / Connector & terminal:
31 / (P5) No. 2—body
33 / (P4) No. 2—body
35 / (P4) No. 4—body
37 / (P5) No. 7—body
61 / (P4) No. 5—body
62 / (P5) No. 6—body
Specified resistance: 1 MΩor more
B4M0420A
4. CHECK HARNESS BETWEEN ABS/TCS CONTROL
MODULE AND HYDRAULIC UNIT.
1) Turn ignition switch OFF.
2) Connect connector to hydraulic unit.
3) Disconnect connector from ABS/TCS control module.
4) Measure resistance between ABS/TCS control module
connector terminals.
TROUBLE CODE / Connector & terminal:
31 / (P5) No. 2—(P6) No. 6
33 / (P4) No. 2—(P6) No. 6
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8. Diagnostics Chart with Trouble Code

35 / (P4) No. 4—(P6) No. 6
37 / (P5) No. 7—(P6) No. 6
61 / (P4) No. 5—(P6) No. 6
62 / (P5) No. 6—(P6) No. 6
Specified resistance: 6.2±1.0Ω
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8. Diagnostics Chart with Trouble Code

E: TROUBLE CODE 32, 34, 36 AND 38
—FAULTY OUTLET SOLENOID VALVE
CIRCUIT(S) IN HYDRAULIC UNIT—
DIAGNOSIS:

Faulty harness/connector

Faulty solenoid valve in hydraulic unit

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS does not operate.

TCS does not operate.

ABS sequence control does not operate.

TCS sequence control does not operate.

Air bleeding mode does not operate.
1. Check resistance of solenoid valve.
OK
Not OK
Replace hydraulic unit.
2. Check body short of solenoid valve.
OK
Not OK
Replace hydraulic unit.
3. Check body short of harness.
OK
Not OK
Repair harness.
4. Check harness between ABS/TCS control
module and hydraulic unit.
OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.




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8. Diagnostics Chart with Trouble Code

B4M0724
B4M0725A
1. CHECK RESISTANCE OF SOLENOID VALVE.
1) Turn ignition switch OFF.
2) Disconnect connector from hydraulic unit.
3) Measure resistance between hydraulic unit terminals.
TROUBLE CODE / Connector & terminal:
32 / (F15) No. 7—No. 9
34 / (F15) No. 8—No. 10
36 / (F15) No. 5—No. 10
38 / (F15) No. 6—No. 9
Specified resistance: 3.5±1.0Ω
B4M0726A
2. CHECK BODY SHORT OF SOLENOID VALVE.
1) Turn ignition switch OFF.
2) Disconnect connector from hydraulic unit.
3) Measure resistance between hydraulic unit terminals.
TROUBLE CODE / Connector & terminal:
32 / (F15) No. 7—body
34 / (F15) No. 8—body
36 / (F15) No. 5—body
38 / (F15) No. 6—body
Specified resistance: 1 MΩor more
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8. Diagnostics Chart with Trouble Code

B4M0424A
3. CHECK BODY SHORT OF HARNESS.
1) Turn ignition switch OFF.
2) Disconnect connector from hydraulic unit.
3) Disconnect connector from ABS/TCS control module.
4) Measure resistance between ABS/TCS control module
connector terminals.
TROUBLE CODE / Connector & terminal:
32 / (P5) No. 3—body
34 / (P4) No. 1—body
36 / (P4) No. 3—body
38 / (P5) No. 8—body
Specified resistance: 1 MΩor more
B4M0425A
4. CHECK HARNESS BETWEEN ABS/TCS CONTROL
MODULE AND HYDRAULIC UNIT.
1) Turn ignition switch OFF.
2) Connect connector to hydraulic unit.
3) Disconnect connector from ABS/TCS control module.
4) Measure resistance between ABS/TCS control module
connector terminals.
TROUBLE CODE / Connector & terminal:
32 / (P5) No. 3—(P6) No. 6
34 / (P4) No. 1—(P6) No. 6
36 / (P4) No. 3—(P6) No. 6
38 / (P5) No. 8—(P6) No. 6
Specified resistance: 3.7±1.0Ω
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8. Diagnostics Chart with Trouble Code

F: TROUBLE CODE 41
—FAULTY ABS/TCS CONTROL
MODULE—
DIAGNOSIS:

Faulty ABS/TCS control module

Faulty harness/connector
TROUBLE SYMPTOM:

ABS does not operate.

TCS does not operate.
1. Check ground circuit of ABS/TCS control
module.
OK
Not OK
Repair harness connector.
2. Check harness connectors between power
supply generator, battery and ABS/TCS con-
trol module.
OK
Not OK
Repair harness/connector.
3. Check sources of signal noise.
OK
Not OK
Repair noise sources.
Replace ABS/TCS control module.
B4M0426



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8. Diagnostics Chart with Trouble Code

B4M0405A
1. CHECK GROUND CIRCUIT OF ABS/TCS CONTROL
MODULE.
1) Turn ignition switch OFF.
2) Disconnect connector from ABS/TCS control module.
3) Measure resistance between ABS/TCS control module
connector and body.
Connector & terminal / Specified resistance:
(P4) No. 6—body / 1Ωor less
(P5) No. 5—body / 1Ωor less
(P7) No. 15—body / 1Ωor less
2. CHECK HARNESS CONNECTORS BETWEEN
POWER SUPPLY GENERATOR, BATTERY AND ABS/
TCS CONTROL MODULE.
Check for poor contacts in plug-in connectors. Refer to
“Basic checks”in“FOREWORD”.
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8. Diagnostics Chart with Trouble Code