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 .

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 .

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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 .

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.

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.



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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.

OK
Not OK
Repair generator.
2. Check battery terminal.

OK
Not OK
Repair battery terminal.
3. Check input voltage of ABS/TCS control mod-
ule.

OK
Not OK
Repair harness/connector.
4. Check ground circuit of ABS/TCS control
module.

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.

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.

OK
Not OK
Repair harness.
3. Check ABS/TCS control module internal
circuits.

OK
Not OK
Replace ABS/TCS control module.
Replace engine control module.
4. Check output voltage of ECM.

Not OK
OK
6. Check open circuit of harness.
OK Not OK
Replace ABS/TCS
control module.
5. Check body short of harness.

OK
Not OK
Repair harness/connector.
Replace engine control module.






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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.

OK
Not OK
Replace valve relay.
2. Check short circuit of valve relay.

OK
Not OK
Replace valve relay.
3. Check ground circuit of valve relay.

OK
Not OK
Repair harness/connector.
4. Check body short of harness.

OK
Not OK
Repair harness.
Replace ABS/TCS control module.




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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.

OK
Not OK
Replace valve relay.
2. Check contact point of valve relay.

OK
Not OK
Replace valve relay.
3. Check input voltage of valve relay.

OK
Not OK
Repair harness/connector.
4. Check harness between ABS/TCS control
module and valve relay.

OK
Not OK
Repair harness/connector.
5. Check resistance of valve relay to ABS/TCS
control module side.

OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.





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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.

OK
Not OK
Repair harness.
2. Check motor operation.

OK
Not OK
Replace motor relay.
3. Check body short of motor sensor.

OK
Not OK
Replace hydraulic unit.
4. Check body short of motor sensor harness.

OK
Not OK
Repair harness.
Replace ABS/TCS control module.




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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.

OK
Not OK
Replace motor relay.
2. Check input voltage of motor relay.

OK
Not OK
Repair harness/connector.
3. Check harness between ABS/TCS control
module and motor relay.

OK
Not OK
Repair harness/connector.
4. Check motor operation.

OK
Not OK
Go to step 9.
5. Check resistance of motor sensor.

OK
Not OK
Replace hydraulic unit.
6. Check body short of motor sensor.

OK
Not OK
Replace hydraulic unit.
7. Check harness between ABS/TCS control
module and motor sensor.

OK
Not OK
Repair harness/connector.
8. Check body short of motor sensor harness.

OK
Not OK
Repair harness.
Replace ABS/TCS control module.








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10. Diagnostic Chart with Select Monitor

9. Check contact point of motor relay.

OK
Not OK
Replace motor relay.
10. Check harness between motor and motor
relay.

OK
Not OK
Repair harness/connector.
11. Check body short of motor harness.

OK
Not OK
Repair harness.
12. Check ground circuit of motor.

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.

OK
Not OK
Replace stroke sensor.
2. Check stroke sensor operation.

OK
Not OK
Replace stroke sensor.
3. Check body short of stroke sensor.

OK
Not OK
Replace stroke sensor.
4. Check harness between stroke sensor and
ABS/TCS control module.

OK
Not OK
Repair harness/connector.
5. Check body short of stroke sensor harness.

OK
Not OK
Repair harness.
Replace ABS/TCS control module.





11 9
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10. Diagnostic Chart with Select Monitor