SUBARU LEGACY 1996 Service Repair Manual

B4M0516
Q: TROUBLE CODE 36
RR.OUT VALVE
—Faulty rear right outlet solenoid valve—
DIAGNOSIS:

Faulty harness/connector

Faulty solenoid valve in hydraulic unit

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS and TCS do not operate.

ABS sequence control does not operate.

TCS sequence control does not operate.

Air bleeding mode does not operate.
NOTE:
The procedures used are the same as those for FR.OUT
VA LV E .
<Ref. to 4-4b [T10M0].>
B4M0517
R: TROUBLE CODE 37
RL.IN VALVE
—Faulty rear left inlet solenoid valve—
DIAGNOSIS:

Faulty harness/connector

Faulty solenoid valve in hydraulic unit

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS and TCS do not operate.

ABS sequence control does not operate.

TCS sequence control does not operate.

Air bleeding mode does not operate.
NOTE:
The procedures used are the same as those for FR.IN
VA LV E .
<Ref. to 4-4b [T10L0].>
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10. Diagnostic Chart with Select Monitor

B4M0518
S: TROUBLE CODE 38
RL.OUT VALVE
—Faulty rear left outlet solenoid valve—
DIAGNOSIS:

Faulty harness/connector

Faulty solenoid valve in hydraulic unit

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS and TCS do not operate.

ABS sequence control does not operate.

TCS sequence control does not operate.

Air bleeding mode does not operate.
NOTE:
The procedures used are the same as those for FR.OUT
VA LV E .
<Ref. to 4-4b [T10M0].>
B4M0519
T: TROUBLE CODE 41
ECU
—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.
<Ref. to 4-4b [T8F1].>
OK
Not OK
Repair harness/connector.
2. Check harness connectors between power
supply generator, battery and ABS/TCS con-
trol module.
<Ref. to 4-4b [T8F2].>
OK
Not OK
Repair harness/connector.
3. Check sources of signal noise.
<Ref. to 4-4b [T8F3].>
OK
Not OK
Repair noise sources.
Replace ABS/TCS control module.



111
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10. Diagnostic Chart with Select Monitor

B4M0520
U: TROUBLE CODE 42
HIGH VOLTAGE
—Source voltage is high—
DIAGNOSIS:

Power source voltage of the ABS/TCS control module is
more than 18 V.

Faulty ABS/TCS control module

Faulty harness/connector
TROUBLE SYMPTOM:

ABS does not operate.

TCS does not operate.
1. Check generator.
<Ref. to 4-4b [T8G1].>
OK
Not OK
Repair generator.
2. Check battery terminal.
<Ref. to 4-4b [T8G2].>
OK
Not OK
Repair battery terminal.
3. Check input voltage of ABS/TCS control mod-
ule.
<Ref. to 4-4b [T8G3].>
OK
Not OK
Repair harness/connector.
4. Check ground circuit of ABS/TCS control
module.
<Ref. to 4-4b [T8G4].>
OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.




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10. Diagnostic Chart with Select Monitor

B4M0521
V: TROUBLE CODE 43
EGI LINE
—Faulty engine control module communication
cables—
DIAGNOSIS:

AET communication cable is broken or short circuited.

AEB communication cable is broken or short circuited.

AEC communication cable is broken or short circuited.

Faulty ABS/TCS control module

Faulty engine control module
TROUBLE SYMPTOM:

TCS does not operate.
1. Check communication cables.
<Ref. to 4-4b [T8H1].>
OK

Terminal voltage
remains at 4—5.4 V.
Replace ABS/TCS control module.

Terminal voltage
remains at 10—14 V.
Go to step 2.

Terminal voltage
remains at2Vorless.
Go to step 4.
Replace ABS/TCS control module.
2. Check harness between ABS/TCS control
module and ECM.
<Ref. to 4-4b [T8H2].>
OK
Not OK
Repair harness.
3. Check ABS/TCS control module internal
circuits.
<Ref. to 4-4b [T8H3].>
OK
Not OK
Replace ABS/TCS control module.
Replace engine control module.
4. Check output voltage of ECM.
<Ref. to 4-4b [T8H4].>
Not OK
OK
6. Check open circuit of harness.
OK Not OK
Replace ABS/TCS
control module.
5. Check body short of harness.
<Ref. to 4-4b [T8H5].>
OK
Not OK
Repair harness/connector.
Replace engine control module.






11 3
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10. Diagnostic Chart with Select Monitor

B4M0522
W: TROUBLE CODE 51
1. V.RELAY ON
—Valve relay ON malfunction—
DIAGNOSIS:

Faulty valve relay

Faulty harness/connector

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS does not operate.

TCS does not operate.
1. Check contact point of valve relay.
<Ref. to 4-4b [T8I2].>
OK
Not OK
Replace valve relay.
2. Check short circuit of valve relay.
<Ref. to 4-4b [T8I3].>
OK
Not OK
Replace valve relay.
3. Check ground circuit of valve relay.
<Ref. to 4-4b [T8I5].>
OK
Not OK
Repair harness/connector.
4. Check body short of harness.
<Ref. to 4-4b [T8I8].>
OK
Not OK
Repair harness.
Replace ABS/TCS control module.




11 4
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10. Diagnostic Chart with Select Monitor

B4M0523
2. V.RELAY OFF
—Valve relay OFF malfunction—
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.
<Ref. to 4-4b [T8I1].>
OK
Not OK
Replace valve relay.
2. Check contact point of valve relay.
<Ref. to 4-4b [T8I2].>
OK
Not OK
Replace valve relay.
3. Check input voltage of valve relay.
<Ref. to 4-4b [T8I4].>
OK
Not OK
Repair harness/connector.
4. Check harness between ABS/TCS control
module and valve relay.
<Ref. to 4-4b [T8I6].>
OK
Not OK
Repair harness/connector.
5. Check resistance of valve relay to ABS/TCS
control module side.
<Ref. to 4-4b [T8I7].>
OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.





11 5
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10. Diagnostic Chart with Select Monitor

B4M0524
X: TROUBLE CODE 52
1. MOTOR ON
—Motor relay ON malfunction—
DIAGNOSIS:

Faulty motor relay

Faulty motor

Faulty motor sensor

Faulty harness

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS does not operate.

TCS does not operate.
1. Check body short of harness.
<Ref. to 4-4b [T8J3].>
OK
Not OK
Repair harness.
2. Check motor operation.
<Ref. to 4-4b [T8J5].>
OK
Not OK
Replace motor relay.
3. Check body short of motor sensor.
<Ref. to 4-4b [T8J7].>
OK
Not OK
Replace hydraulic unit.
4. Check body short of motor sensor harness.
<Ref. to 4-4b [T8J9].>
OK
Not OK
Repair harness.
Replace ABS/TCS control module.




11 6
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10. Diagnostic Chart with Select Monitor

B4M0525
2. MOTOR OFF
—Motor relay OFF malfunction—
DIAGNOSIS:

Faulty motor relay

Faulty motor

Faulty motor sensor

Faulty harness/connector

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS and TCS do not operate.
1. Check resistance of motor relay.
<Ref. to 4-4b [T8J1].>
OK
Not OK
Replace motor relay.
2. Check input voltage of motor relay.
<Ref. to 4-4b [T8J2].>
OK
Not OK
Repair harness/connector.
3. Check harness between ABS/TCS control
module and motor relay.
<Ref. to 4-4b [T8J4].>
OK
Not OK
Repair harness/connector.
4. Check motor operation.
<Ref. to 4-4b [T8J5].>
OK
Not OK
Go to step 9.
5. Check resistance of motor sensor.
<Ref. to 4-4b [T8J6].>
OK
Not OK
Replace hydraulic unit.
6. Check body short of motor sensor.
<Ref. to 4-4b [T8J7].>
OK
Not OK
Replace hydraulic unit.
7. Check harness between ABS/TCS control
module and motor sensor.
<Ref. to 4-4b [T8J8].>
OK
Not OK
Repair harness/connector.
8. Check body short of motor sensor harness.
<Ref. to 4-4b [T8J9].>
OK
Not OK
Repair harness.
Replace ABS/TCS control module.








11 7
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10. Diagnostic Chart with Select Monitor

9. Check contact point of motor relay.
<Ref. to 4-4b [T8J10].>
OK
Not OK
Replace motor relay.
10. Check harness between motor and motor
relay.
<Ref. to 4-4b [T8J11].>
OK
Not OK
Repair harness/connector.
11. Check body short of motor harness.
<Ref. to 4-4b [T8J12].>
OK
Not OK
Repair harness.
12. Check ground circuit of motor.
<Ref. to 4-4b [T8J13].>
OK
Not OK
Repair harness/connector.
Replace hydraulic unit.
NOTE:
The check can also be made by analyzing the sensor out-
put signal with oscilloscope during the TCS sequence con-
trol operation. If the ECM female connector end gives cor-
rect value, skip steps 5 through 8.
If not, operate the TCS sequence control again and mea-
sure the value at motor sensor male connector end, with
the motor sensor connector disconnected. If the value is
OK, proceed with steps 7 through 8 above.




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10. Diagnostic Chart with Select Monitor

B4M0526
Y: TROUBLE CODE 54
1. B.SW HARD
—Break and short circuit at stroke sensor or its
wiring—
DIAGNOSIS:

Faulty stroke sensor

Faulty harness/connector

Faulty stop light switch

Faulty ABS/TCS control module
TROUBLE SYMPTOM:

ABS and TCS do not operate.
NOTE:
Operate the function F09 in select monitor TCS mode, and
read the sensor output step.
If system is normal, the output reading is 1 when brake
pedal is not depressed, and it changes from 2 to 3, 4 and
5 in accordance with the brake pedal depressing. If so, skip
check steps 1 through 5.
1. Check resistance of stroke sensor.
<Ref. to 4-4b [T8K2].>
OK
Not OK
Replace stroke sensor.
2. Check stroke sensor operation.
<Ref. to 4-4b [T8K3].>
OK
Not OK
Replace stroke sensor.
3. Check body short of stroke sensor.
<Ref. to 4-4b [T8K4].>
OK
Not OK
Replace stroke sensor.
4. Check harness between stroke sensor and
ABS/TCS control module.
<Ref. to 4-4b [T8K10].>
OK
Not OK
Repair harness/connector.
5. Check body short of stroke sensor harness.
<Ref. to 4-4b [T8K11].>
OK
Not OK
Repair harness.
Replace ABS/TCS control module.





11 9
4-4bBRAKES
10. Diagnostic Chart with Select Monitor