SUBARU LEGACY 1997 Service Repair Manual

B4M0895B
3) Measure resistance between motor relay installing point
and relay box connector.
: Connector & terminal
Motor relay installing point No. 86—To
(F50) No. 4
Is resistance less than 0.5Ω?
: Go to step8L11.
: Replace relay box.
B4M0896
8L11CHECK GROUND SHORT IN CONTROL
CIRCUIT OF RELAY BOX.
Measure resistance between relay box and chassis
ground.
: Connector & terminal
Motor relay installing point No. 86—Chas-
sis ground
Motor relay installing point No. 85—Chas-
sis ground
Is resistance more than 1 MΩ?
: Go to step8L12.
: Replace relay box. Check fuse No. 19.
B4M0897
8L12CHECK BATTERY SHORT IN CONTROL
CIRCUIT OF RELAY BOX.
1) Turn ignition switch to ON.
2) Measure voltage between motor relay installing point
and chassis ground.
: Connector & terminal
Motor relay installing point (+) No. 86—
Chassis ground ()
Motor relay installing point (+) No. 85—
Chassis ground ()
Is voltage 0 V?
: Go to next step.
: Replace relay box and check all fuses.
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4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

3) Turn ignition switch to OFF.
4) Measure voltage between motor relay installing point
and chassis ground.
: Connector & terminal
Motor relay installing point (+) No. 86—
Chassis ground
Motor relay installing point (+) No. 85—
Chassis ground
Is voltage 0 V?
: Go to step8L13.
: Replace relay box and check all fuses.
B4M0898B
8L13CHECK BROKEN WIRE IN MONITOR
SYSTEM HARNESS.
1) Connect between terminals No. 10 and No. 1 of
ABSCM connector (F49) with a lead wire.
2) Measure resistance between relay box connector and
chassis ground.
: Connector & terminal
(F50) No. 6—Chassis ground
Is resistance less than 0.5Ω?
: Go to step8L14.
: Repair harness connector between ABSCM and
relay box.
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4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

B4M0899A
8L14CHECK BROKEN WIRE IN RELAY CON-
TROL SYSTEM HARNESS.
1) Connect valve relay and motor relay to relay box.
2) Connect connector (F50) to relay box.
3) Connect connector to hydraulic unit.
4) Measure resistance between ABSCM connector and
chassis ground.
: Connector & terminal
(F49) No. 22—Chassis ground
Is resistance 80±10Ω?
: Go to step8L15.
: Repair harness connector between ABSCM and
relay box.
B4M0900A
8L15CHECK GROUND SHORT BETWEEN
RELAY BOX AND ABSCM.
1) Disconnect connector (F50) from relay box.
2) Measure resistance between ABSCM connector and
chassis ground.
: Connector & terminal
(F49) No. 22—Chassis ground
(F49) No. 10—Chassis ground
Is resistance more than 1 MΩ?
: Go to step8L16.
: Repair harness between ABSCM and relay box.
Check fuse No. 19 and SBF6.
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4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

B4M0901A
8L16CHECK BATTERY SHORT BETWEEN
RELAY BOX AND ABSCM.
1) Turn ignition switch to ON.
2) Measure voltage between ABSCM and chassis ground.
: Connector & terminal
(F49) No. 22 (+)—Chassis ground ()
(F49) No. 10 (+)—Chassis ground ()
Is voltage 0 V?
: Go to next step.
: Repair harness between relay box and ABSCM.
Check fuse SBF6.
3) Turn ignition switch to OFF.
4) Measure voltage between ABSCM and chassis ground.
: Connector & terminal
(F49) No. 22 (+)—Chassis ground ()
(F49) No. 10 (+)—Chassis ground ()
Is voltage 0 V?
: Go to step8L17.
: Repair harness between relay box and ABSCM.
Check fuse SBF6.
B4M0902A
8L17CHECK GROUND SHORT AT ABSCM
MONITOR TERMINAL.
Measure resistance between ABSCM terminals.
: Connector & terminal
To (F49) No. 10—No. 1
Is resistance less than 0.5Ω?
: Go to step8L18.
: Replace ABSCM.
B4M0903A
8L18CHECK BATTERY SHORT AT ABSCM
MONITOR TERMINAL.
1) Disconnect connector cover from ABSCM connector.

2) Connect all connectors.
3) Turn ignition switch to ON.
4) Measure voltage between ABSCM connector terminals.
: Connector & terminal
(F49) No. 10 (+)—No.1()
Is voltage less than 2 V?
: Go to next step.
: Replace ABSCM.
5) Turn ignition switch to OFF.
6) Measure voltage between ABSCM connector terminals.
: Connector & terminal
(F49) No. 10 (+)—No.1()
Is voltage less than 2 V?
: Go to step8L19.
: Replace ABSCM.
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4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

B4M0808
8L19
CHECK MOTOR GROUND.
: Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
Is the motor ground terminal tightly
clamped?
: Go to step8L20.
: Tighten the clamp of motor ground terminal.
B4M0904A
8L20CHECK ABSCM MOTOR DRIVE TERMI-
NAL.
1) Measure voltage between ABSCM connector terminals.
2) Operate the check sequence.
: Connector & terminal
(F49) No. 22 (+)—No.1()
Does the voltage drop from 10—13Vto
less than 1.5 V, and rise to 10—13 V again
when carrying out the check sequence?
: Go to step8L21.
: Replace ABSCM.
B4M0905A
8L21
CHECK MOTOR OPERATION.
1) Measure voltage between ABSCM connector terminals.
2) Operate the check sequence.
: Connector & terminal
(F49) No. 10 (+)—No.1()
Does the voltage raise from less than 1.5 V
to 10—13 V, and return to less than 1.5 V
again when carrying out the check
sequence?
Can motor revolution noise (buzz) be heard
when carrying out the check sequence?
: Go to step8L22.
: Replace hydraulic unit.
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4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

8L22CHECK POOR CONTACT IN CONNEC-
TOR BETWEEN HYDRAULIC UNIT,
RELAY BOX AND ABSCM.
: Is there poor contact in connector between
hydraulic unit, relay box and ABSCM?
: Repair connector.
: Go to step8L23.
8L23
CHECK ABSCM.
1) Connect all connectors.
2) Erase the memory.
3) Perform inspection mode.
4) Read out the trouble code.
: Is the same trouble code as in the current
diagnosis still being output?
: Replace ABSCM.
: Go to next.
: Are other trouble codes being output?
: Proceed with the diagnosis corresponding to the
trouble code.
: A temporary poor contact.
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4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

M: TROUBLE CODE 54
—ABNORMAL STOP LIGHT SWITCH—
DIAGNOSIS:

Faulty stop light switch
TROUBLE SYMPTOM:

ABS does not operate.
8M1.Check if stop lights come on.
8M2.Check open circuit of harness.
8M3.Check poor contact in connector between
stop light switch and ABSCM.
8M4.Check ABSCM.



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8. Diagnostics Chart with Trouble Code

WIRING DIAGRAM:
B4M1041
8M1
CHECK IF STOP LIGHTS COME ON.
Depress the brake pedal.
: Do stop lights turn on?
: Go to step8M2.
: Repair stop lights circuit.
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4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

B4M0908A
8M2
CHECK OPEN CIRCUIT OF HARNESS.
1) Turn ignition switch to OFF.
2) Disconnect connector from ABSCM.
3) Depress brake pedal.
4) Measure voltage between ABSCM connector and chas-
sis ground.
: Connector & terminal
(F49) No. 36—Chassis ground
Is voltage 10—13 V?
: Go to step8M3.
: Repair harness between stop light switch and
ABSCM.
8M3CHECK POOR CONTACT IN CONNEC-
TOR BETWEEN STOP LIGHT SWITCH
AND ABSCM.
: Is there poor contact in connector between
stop light switch and ABSCM?
: Repair connector.
: Go to step8M4.
8M4
CHECK ABSCM.
1) Connect all connectors.
2) Erase the memory.
3) Perform inspection mode.
4) Read out the trouble code.
: Is the same trouble code as in the current
diagnosis still being output?
: Replace ABSCM.
: Go to next.
: Are other trouble codes being output?
: Proceed with the diagnosis corresponding to the
trouble code.
: A temporary poor contact.
104
4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

N: TROUBLE CODE 56
—ABNORMAL G SENSOR OUTPUT
VOLTAGE—
DIAGNOSIS:

Faulty G sensor output voltage
TROUBLE SYMPTOM:

ABS does not operate.
8N1.Check all four wheels for free turning.
8N2.Check specifications of ABSCM.
8N3.Check input voltage of G sensor.
8N4.Check broken wire in G sensor output harness
and ground harness.
8N5.Check ground short in G sensor output
harness.
8N6.Check battery short of harness.
8N7.Check G sensor.
8N8.Check poor contact in connector between
ABSCM and G sensor.
8N9.Check ABSCM.








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4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code