SUBARU LEGACY 1995 Service Repair Manual
Manufacturer: SUBARU, Model Year: 1995, Model line: LEGACY, Model: SUBARU LEGACY 1995Pages: 2248, PDF Size: 48.81 MB
Page 1661 of 2248
H: TROUBLE CODE 42
—SOURCE VOLTAGE IS LOW.—
DIAGNOSIS:
Faulty battery
Faulty A.B.S. control module
Faulty harness
Faulty valve relay
TROUBLE SYMPTOM:
A.B.S. does not operate.
Check battery.
OK
Not OK
Replace battery.
1. Check input voltage of A.B.S. control module.
Not OK
OK
Replace A.B.S. control module.
2. Check input voltage of hydraulic control unit.
OK
Not OK
Repair harness/connector.
3. Check harness connector between A.B.S. con-
trol module and hydraulic control unit.
OK
Not OK
Repair harness/connector.
4. Check valve relay.
OK
Not OK
Replace valve relay.
Replace hydraulic control unit.
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7. Diagnostics Chart with Trouble Code
Page 1662 of 2248
B4M0596
B4M0261B
1. CHECK INPUT VOLTAGE OF A.B.S. CONTROL
MODULE.
1) Turn ignition switch OFF.
2) Disconnect connector from A.B.S. control module.
3) Disconnect connector cover from connector.
4) Connect connector to A.B.S. control module.
5) Turn ignition switch ON.
6) Measure input voltage between A.B.S. control module
connector and body.
Connector & terminal / Specified voltage:
(P3) No. 32—Body / 10—12 V
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7. Diagnostics Chart with Trouble Code
Page 1663 of 2248
B4M0262B
2. CHECK INPUT VOLTAGE OF HYDRAULIC
CONTROL UNIT.
1) Turn ignition switch OFF.
2) Disconnect connector from hydraulic control unit.
3) Turn ignition switch ON.
4) Measure input voltage between hydraulic control unit
connector and body.
Connector & terminal / Specified voltage:
(F8) No. 1—Body / 10—12 V
B4M0263B
3. CHECK HARNESS CONNECTOR BETWEEN A.B.S.
CONTROL MODULE AND HYDRAULIC CONTROL
UNIT.
1) Turn ignition switch OFF.
2) Disconnect connector from A.B.S. control module and
hydraulic control unit.
3) Measure resistance between A.B.S. control module and
hydraulic control unit.
Connector & terminal / Specified resistance:
(P3) No. 32—(F9) No. 11 / 0Ω
G4M0690
4. CHECK VALVE RELAY.
1) Remove valve relay.
2) Attach circuit tester probes to terminals, as shown in
figure.
3) Measure resistance between respective terminals.
Terminal / Specified resistance:
No. 87—No. 30 / 0Ω(when 12 volts applied.)
No. 87—No.30/1MΩ(when no volts applied.)
No. 87a—No.30/1MΩ(when 12 volts applied.)
No. 87a—No. 30 / 0Ω(when no volts applied.)
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7. Diagnostics Chart with Trouble Code
Page 1664 of 2248
I: TROUBLE CODE 51
—FAULTY VALVE RELAY—
DIAGNOSIS:
Faulty valve relay
Faulty harness
Faulty A.B.S. control module
TROUBLE SYMPTOM:
A.B.S. does not operate.
1. Check power supply circuit of A.B.S. control
module.
OK
Not OK
Repair harness/connector.
2. Check output voltage to A.B.S. control
module.
OK
Not OK
Replace A.B.S. control module.
3. Check input voltage of A.B.S. control module.
Not OK
OK
Replace A.B.S. control module.
4. Check harness connector between A.B.S.
control module and hydraulic control unit.
OK
Not OK
Repair harness/connector.
5. Check power supply circuit of hydraulic
control unit.Not OK
Repair harness/connector.
6. Check valve relay.Replace valve relay.
Replace hydraulic control unit.
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7. Diagnostics Chart with Trouble Code
Page 1665 of 2248
B4M0600
B4M0266B
1. CHECK POWER SUPPLY CIRCUIT OF A.B.S.
CONTROL MODULE.
1) Turn ignition switch OFF.
2) Disconnect connector from A.B.S. control module.
3) Turn ignition switch ON.
4) Measure voltage between A.B.S. control module con-
nector terminals.
Connector & terminal / Specified voltage:
(P3) No. 1—No. 20 / 10—12 V
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7. Diagnostics Chart with Trouble Code
Page 1666 of 2248
B4M0267B
2. CHECK OUTPUT VOLTAGE TO A.B.S. CONTROL
MODULE.
1) Turn ignition switch OFF.
2) Disconnect connector from A.B.S. control module.
3) Disconnect connector cover from connector.
4) Connect connector to A.B.S. control module.
5) Turn ignition switch ON.
6) Measure voltage between A.B.S. control module con-
nector terminals.
Connector & terminal / Specified voltage:
(P3) No. 17—No. 20 / 10—12 V
B4M0268B
3. CHECK INPUT VOLTAGE OF A.B.S. CONTROL
MODULE.
1) Turn ignition switch ON.
2) Measure voltage between A.B.S. control module con-
nector terminals.
Connector & terminal / Specified voltage:
(P3) No. 32—No. 20 / 10—12 V
B4M0269B
4. CHECK HARNESS CONNECTOR BETWEEN A.B.S.
CONTROL MODULE AND HYDRAULIC CONTROL
UNIT.
1) Turn ignition switch OFF.
2) Disconnect connector from A.B.S. control module and
hydraulic control unit.
3) Measure resistance between A.B.S. control module and
hydraulic control unit.
Connector & terminal / Specified resistance:
(P3) No. 17—(F9) No.6/0Ω
(P3) No. 32—(F9) No. 11 / 0Ω
(P3) No. 27—(F9) No. 12 / 0Ω
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7. Diagnostics Chart with Trouble Code
Page 1667 of 2248
B4M0262B
5. CHECK POWER SUPPLY CIRCUIT OF HYDRAULIC
CONTROL UNIT.
1) Turn ignition switch OFF.
2) Disconnect connector from hydraulic control unit.
3) Turn ignition switch ON.
4) Measure voltage between hydraulic control unit and
body.
Connector & terminal / Specified voltage:
(F8) No. 1—Body / 10—12 V
G4M0690
6. CHECK VALVE RELAY.
1) Remove valve relay.
2) Attach circuit tester probes to terminals, as shown in
figure.
3) Measure resistance between respective terminals.
Terminal / Specified resistance:
No. 87—No. 30 / 0Ω(when 12 volts applied.)
No. 87—No.30/1MΩ(when no volts applied.)
No. 87a—No.30/1MΩ(when 12 volts applied.)
No. 87a—No. 30 / 0Ω(when no volts applied.)
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7. Diagnostics Chart with Trouble Code
Page 1668 of 2248
J: TROUBLE CODE 52
—FAULTY HYDRAULIC MOTOR AND/OR
MOTOR RELAY—
DIAGNOSIS:
Faulty motor relay
Faulty hydraulic control unit
Faulty harness
Faulty A.B.S. control module
TROUBLE SYMPTOM:
A.B.S. does not operate.
1. Check power supply circuit of A.B.S. control
module.
OK
Not OK
Repair harness/connector.
2. Check output voltage of A.B.S. control
module.
OK
Not OK
Replace A.B.S. control module.
3. Check harness connector between A.B.S.
control module and hydraulic control unit.
OK
Not OK
Repair harness/connector.
4. Check power supply circuit of hydraulic
control unit.
OK
Not OK
Repair harness/connector.
5. Check motor relay.
OK
Not OK
Replace motor relay.
Check hydraulic motor ground harness.
OK
Not OK
Repair ground harness.
Replace hydraulic control unit.
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7. Diagnostics Chart with Trouble Code
Page 1669 of 2248
B4M0605
B4M0266B
1. CHECK POWER SUPPLY CIRCUIT OF A.B.S.
CONTROL MODULE.
1) Turn ignition switch OFF.
2) Disconnect connector from A.B.S. control module.
3) Turn ignition switch ON.
4) Measure voltage between A.B.S. control module con-
nector terminals.
Connector & terminal / Specified voltage:
(P3) No. 1—No. 20 / 10—12 V
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7. Diagnostics Chart with Trouble Code
Page 1670 of 2248
B4M0267B
2. CHECK OUTPUT VOLTAGE OF A.B.S. CONTROL
MODULE.
1) Turn ignition switch OFF.
2) Disconnect connector from A.B.S. control module.
3) Disconnect connector cover from connector.
4) Connect connector to A.B.S. control module.
5) Turn ignition switch ON.
6) Measure voltage between A.B.S. control module con-
nector terminals.
Connector & terminal / Specified voltage:
(P3) No. 17—No. 20 / 10—12 V
B4M0275B
3. CHECK HARNESS CONNECTOR BETWEEN A.B.S.
CONTROL MODULE AND HYDRAULIC CONTROL
UNIT.
1) Turn ignition switch OFF.
2) Disconnect connector from A.B.S. control module.
3) Disconnect connector from hydraulic control unit.
4) Measure resistance between A.B.S. control module
connector and hydraulic control unit connector.
Connector & terminal / Specified resistance:
(P3) No. 17—(F9) No.6/0Ω
(P3) No. 28—(F9) No.5/0Ω
(P3) No. 14—(F9) No.7/0Ω
B4M0276B
4. CHECK POWER SUPPLY CIRCUIT OF HYDRAULIC
CONTROL UNIT.
1) Turn ignition switch OFF.
2) Disconnect connector from hydraulic control unit.
3) Measure voltage between hydraulic control unit connec-
tor and body.
Connector & terminal / Specified voltage:
(F8) No. 2—Body / 10—12 V
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7. Diagnostics Chart with Trouble Code