SUBARU LEGACY 1996 Service Repair Manual

B4M0456A
8. CHECK HARNESS BETWEEN ABS/TCS CONTROL
MODULE AND MOTOR SENSOR.
1) Turn ignition switch OFF.
2) Connect motor sensor connector.
3) Disconnect ABS/TCS control module.
4) Measure resistance between ABS/TCS control module
connector terminals.
Connector & terminal / Specified resistance:
(P7) No. 3—No. 13 / 72—98Ω
B4M0457A
9. CHECK BODY SHORT OF MOTOR SENSOR
HARNESS.
1) Turn ignition switch OFF.
2) Connect motor sensor connector.
3) Disconnect ABS/TCS control module.
4) Measure resistance between ABS/TCS control module
and body.
Connector & terminal / Specified resistance:
(P7) No. 3—body/1MΩor more
(P7) No. 13—body/1MΩor more
B4M0458A
10. CHECK CONTACT POINT OF MOTOR RELAY.
1) Connect motor relay.
2) Connect ABS/TCS control module.
3) Operate the TCS sequence check. [W20F0].>
4) Measure voltage between motor relay connector and
body.
Connector & terminal / Specified voltage:
(F10) No. 4—body / 10—14 V (While TCS oper-
ating indicator light is ON.)
B4M0459A
11. CHECK HARNESS BETWEEN MOTOR AND
MOTOR RELAY.
1) Turn ignition switch OFF.
2) Disconnect motor relay.
3) Disconnect motor connector.
4) Measure resistance between motor relay connector and
motor connector.
Connector & terminal / Specified resistance:
(F13) No. 2—(F10) No.4/1Ωor less
B4M0460A
12. CHECK BODY SHORT OF MOTOR HARNESS.
1) Turn ignition switch OFF.
2) Disconnect motor relay.
3) Disconnect motor connector.
4) Measure resistance between motor connector and
body.
Connector & terminal / Specified resistance:
(F13) No. 2—body/1MΩor more
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8. Diagnostics Chart with Trouble Code

B4M0461A
13. CHECK GROUND CIRCUIT OF MOTOR.
1) Turn ignition switch OFF.
2) Disconnect motor connector.
3) Measure resistance between motor connector and
body.
Connector & terminal / Specified resistance:
(F13) No. 1—body / 1Ωor less
NOTE:
The check can also be made by analyzing the waves of the
motor sensor output signal with oscilloscope during the
TCS sequence control operation. If the ECM female con-
nector end gives correct value, skip steps 6 through 9
above.
If not, operate the TCS sequence control again and mea-
sure the value at motor sensor male connector end with the
motor sensor connector removed. If the value is OK, pro-
ceed with steps 8 and 9 above.
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8. Diagnostics Chart with Trouble Code

K: TROUBLE CODE 54
—FAULTY STROKE SENSOR AND/OR STOP
LIGHT SWITCH—
DIAGNOSIS:

Faulty stroke sensor

Faulty stop light switch

Faulty pump unit in hydraulic unit

Faulty ABS/TCS control module

Faulty harness/connector
TROUBLE SYMPTOM:

ABS and TCS do not operate.

No kick-back ocuurs while ABS is functioning.

Only when the stop light switch circuit is broken, the ABS
functions while TCS does not. (TCS warning light only illu-
minates.)
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8. Diagnostics Chart with Trouble Code

1. Check correct installation of stroke sensor.
OK
Not OK
Repair stroke sensor.
2. Check resistance of stroke sensor.
OK
Not OK
Replace stroke sensor.
3. Check stroke sensor operation.
OK
Not OK
Replace stroke sensor.
4. Check body short of stroke sensor.
OK
Not OK
Replace stroke sensor.
5. Check contact point of stop light switch.
OK
Not OK
Replace stroke sensor.
6. Check body short of stop light switch.
OK
Not OK
Replace stroke sensor.
7. Check power supply of stop light switch.
OK
Not OK
Repair harness/connector.
8. Check input voltage of ABS/TCS control mod-
ule.
OK
Not OK
Repair harness/connector.
9. Check stop light circuit.
OK
Not OK
Repair harness/connector.
Replace stop light bulb and/or fuse.
10. Check harness between stroke sensor and
ABS/TCS control module.
OK
Not OK
Repair harness/connector.
11. Check body short of stroke sensor harness.
OK
Not OK
Repair harness.
12. Check pump unit operation.
OK
Not OK
Replace hydraulic unit.
Replace ABS/TCS control module.












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8. Diagnostics Chart with Trouble Code

B4M0732
1. CHECK CORRECT INSTALLATION OF STROKE
SENSOR.
1) Check that the stroke sensor is firmly installed without
play.
2) Check that the stop lamp does not remain illuminated.
B4M0463A
2. CHECK RESISTANCE OF STROKE SENSOR.
1) Turn ignition switch OFF.
2) Disconnect stroke sensor connectors.
3) Remove stroke sensor.
4) Measure resistance between stroke sensor terminals.
Terminal / Specified resistance:
No. 1—No. 3 / 570—630Ω
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8. Diagnostics Chart with Trouble Code

B4M0464A
3. CHECK STROKE SENSOR OPERATION.
1) Turn ignition switch OFF.
2) Disconnect stroke sensor connectors.
3) Remove stroke sensor.
4) Measure the stroke sensor resistance against the rod
stroke.
Terminal:
No. 3—No. 2
Stroke
Unit: mm (in)Specified
resistance
0—3.1±0.5 (0—0.122±0.020) 95—105Ω
3.1—5.5±0.5 (0.122—0.217±0.020) 190—210Ω
5.5—7.9±0.5 (0.217—0.311±0.020) 285—315Ω
7.9—10.3±0.5 (0.311—0.406±0.020) 380—420Ω
10.3—18±0.5 (0.406—0.709±0.020) 475—525Ω
NOTE:
Stroke = 0 when the stroke sensor rod is completely drawn
into the sensor unit.
B4M0465A
4. CHECK BODY SHORT OF STROKE SENSOR.
1) Turn ignition switch OFF.
2) Disconnect stroke sensor connectors.
3) Remove stroke sensor.
4) Measure resistance between stroke sensor terminal
and stroke sensor threads.
Terminal / Specified resistance:
No. 1—stroke sensor threads/ 1 MΩor more
No. 2—stroke sensor threads/ 1 MΩor more
No. 3—stroke sensor threads/ 1 MΩor more
B4M0466A
5. CHECK CONTACT POINT OF STOP LIGHT
SWITCH.
1) Turn ignition switch OFF.
2) Disconnect stroke sensor connectors.
3) Remove stroke sensor.
4) Measure resistance between stroke sensor terminals.
Terminal:
No. 2—No. 3
Stroke
Unit mm (in)Specified
resistance
0—2.2±1.0 (0—0.087±0.039) 1 MΩor more
2.2±1.0—18.0±0.5 (0.087±0.039—0.709±0.020) 1Ωor less
NOTE:
Stroke = 0 when the rod is completely drawn in.
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8. Diagnostics Chart with Trouble Code

B4M0467A
6. CHECK BODY SHORT OF STOP LIGHT SWITCH.
1) Turn ignition switch OFF.
2) Disconnect stroke sensor connectors.
3) Remove stroke sensor.
4) Measure resistance between stroke sensor terminal
and stroke sensor threads.
Terminal / Specified resistance:
No. 2—stroke sensor threads/1MΩor more
No. 3—stroke sensor threads/1MΩor more
B4M0468A
7. CHECK POWER SUPPLY OF STOP LIGHT
SWITCH.
1) Turn ignition switch OFF.
2) Disconnect stroke sensor connector.
3) Measure voltage between stroke sensor connector and
body.
Connector & terminal / Specified voltage:
(B67) No. 3—body / 10—13 V
B4M0469A
8. CHECK INPUT VOLTAGE OF ABS/TCS CONTROL
MODULE.
1) Turn ignition switch OFF.
2) Install stroke sensor.
3) Connect stop light switch connector.
4) Disconnect ABS/TCS control module connector.
5) Measure voltage between ABS/TCS control module
connector and body.
Connector & terminal / Specified voltage:
(P7) No. 7—body / 10—13 V (With brake pedal
depressed)
(P7) No. 7—body/0V(Without brake pedal
depressed)
9. CHECK STOP LIGHT CIRCUIT.
1) Turn ignition switch OFF.
2) Install stroke sensor.
3) Connect stroke sensor connector.
4) Connect ABS/TCS control module connector.
5) Depress brake pedal and check that the stop light
comes on.
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8. Diagnostics Chart with Trouble Code

B4M0470A
10. CHECK HARNESS BETWEEN STROKE SENSOR
AND ABS/TCS CONTROL MODULE.
1) Turn ignition switch OFF.
2) Install stroke sensor.
3) Connect stroke sensor connector.
4) Disconnect ABS/TCS control module connector.
5) Measure resistance between ABS/TCS control module
connector terminals.
Connector & terminal / Specified resistance:
(P7) No. 4—No. 14 / 570—630Ω
(P7) No. 5—No. 14 / 95—105Ω
NOTE:
Do not depress brake pedal.
B4M0471A
11. CHECK BODY SHORT OF STROKE SENSOR
HARNESS.
1) Turn ignition switch OFF.
2) Connect stroke sensor connector.
3) Disconnect ABS/TCS control module connector.
4) Measure resistance between ABS/TCS control module
connector and body.
Connector & terminal / Specified resistance:
(P7) No. 4—body/1MΩor more
(P7) No. 5—body/1MΩor more
(P7) No. 14—body/1MΩor more
12. CHECK PUMP UNIT OPERATION.
1) Turn ignition switch OFF.
2) Connect stroke sensor connector.
3) Connect stop light switch connector.
4) Connect ABS/TCS control module connector.
5) Operate the TCS sequence control and check that the
front brake fluid pressure increases and decreases cor-
rectly.
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8. Diagnostics Chart with Trouble Code

L: TROUBLE CODE 57
—FAULTY FLUID LEVEL SENSOR—
DIAGNOSIS:

Faulty fluid level sensor circuit

Faulty harness/connector

Faulty ABS/TCS control module

Faulty generator
TROUBLE SYMPTOM:

ABS does not operate.

TCS does not operate.
1. Check engine trouble code.
Ye sNO
5. Check generator function.
OK
Not OK
Repair generator.
6. Check input voltage of ABS/TCS control
module.
OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.
2. Check input voltage of ABS/TCS control module.
OK
Not OK
Repair harness/connector.
3. Check ground short of harness.
OK
Not OK
Repair harness.
4. Check ground circuit of ABS/TCS control module.
OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.






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8. Diagnostics Chart with Trouble Code

B4M0743
1. CHECK ENGINE TROUBLE CODE.
1) Read out engine trouble code.
2) Is trouble code 39 in memory?
B4M0395A
2. CHECK INPUT VOLTAGE OF ABS/TCS CONTROL
MODULE.
1) Turn ignition switch OFF.
2) Disconnect ABS/TCS control module connectors.
3) Turn ignition switch ON, while engine is idling.
4) Measure voltage between ABS/TCS control module
connector and body.
Connector & terminal / Specified voltage:
(P5) No. 1—body / 14.5±0.3 V
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8. Diagnostics Chart with Trouble Code