1997 SUBARU LEGACY battery

B4M0970
AE: 52 M. RELAY ON
—MOTOR RELAY ON FAILURE—
DIAGNOSIS:

Faulty motor

Faulty motor relay

Faulty harness connector
TROUBLE SYMPTOM:

ABS does not operate.
10AE1.Check resistance of motor relay.
10AE2.Check contact point of motor relay.
10AE3.Check short of motor relay.
10AE4.Check battery short in contact point circuit of
relay box.
10AE5.Check ground short in control circuit of relay
box.
10AE6.Check ground short between relay box and
ABSCM.
10AE7.Check battery short between relay box and
ABSCM.
10AE8.Check battery short at ABSCM monitor
terminal.
10AE9.Check motor ground.
10AE10.Check ABSCM motor drive terminal.
10AE11.Check motor operation.
10AE12.Check poor contact in connector between
hydraulic unit, relay box and ABSCM.
10AE13.Check ABSCM.












234
4-4cBRAKES [ABS 5.3 TYPE]
10. Diagnostics Chart with Select Monitor

B4M0887A
10AE2CHECK CONTACT POINT OF MOTOR
RELAY.
1) Connect battery to motor relay terminals No. 85 and No.
86.
2) Measure resistance between motor relay terminals.
: Terminals
No. 30—No. 87
Is resistance less than 0.5Ω?
: Go to next step.
: Replace motor relay.
B4M0888A
3) Disconnect battery from motor relay terminals.
4) Measure resistance between motor relay terminals.
: Terminals
No. 30—No. 87
Is resistance more than 1 MΩ?
: Go to step10AE3.
: Replace motor relay.
B4M0889A
10AE3
CHECK SHORT OF MOTOR RELAY.
Measure resistance between motor relay terminals.
: Terminals
No. 85—No. 30
No. 85—No. 87
Is resistance more than 1 MΩ?
: Go to step10AE4.
: Replace motor relay.
236
4-4cBRAKES [ABS 5.3 TYPE]
10. Diagnostics Chart with Select Monitor

B4M0793A
10AE4CHECK BATTERY SHORT IN CONTACT
POINT CIRCUIT OF RELAY BOX.
1) Disconnect connector from ABSCM.
2) Disconnect connector (ABS1) from hydraulic unit.
3) Turn ignition switch to ON.
4) Measure voltage between relay box connector and
chassis ground.
: Connector & terminal
(ABS1) No. 1 (+)—Chassis ground ()
Is voltage 0 V?
: Go to next step.
: Replace relay box.
5) Turn ignition switch to OFF.
6) Measure voltage between relay box connector and
chassis ground.
: Connector & terminal
(ABS1) No. 1 (+)—Chassis ground ()
Is voltage 0 V?
: Go to step10AE5.
: Replace relay box.
B4M1032
10AE5CHECK GROUND SHORT IN CONTROL
CIRCUIT OF RELAY BOX.
1) Disconnect connector (F50) from relay box.
2) Measure resistance between relay box and chassis
ground.
: Connector & terminal
Motor relay installing point No. 85—Chas-
sis ground
Motor relay installing point No. 86—Chas-
sis ground
Is resistance more than 1 MΩ?
: Go to step10AE6.
: Replace relay box. Check fuse No. 19.
237
4-4cBRAKES [ABS 5.3 TYPE]
10. Diagnostics Chart with Select Monitor

B4M0900A
10AE6CHECK GROUND SHORT BETWEEN
RELAY BOX AND ABSCM.
1) Disconnect connector (F49) from ABSCM.
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 step10AE7.
: Repair harness between ABSCM and relay box.
Check fuse No. 19 and SBF6.
B4M0901A
10AE7CHECK 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 step10AE8.
: Repair harness between relay box and ABSCM.
Check fuse SBF6.
238
4-4cBRAKES [ABS 5.3 TYPE]
10. Diagnostics Chart with Select Monitor

B4M0903A
10AE8CHECK 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 & terminals
(F49) No. 10 (+)—No.1()
Is voltage less than 2 V?
: Go to step10AE9.
: Replace ABSCM.
B4M0808
10AE9
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 step10AE10.
: Tighten the clamp of motor ground terminal.
B4M0904A
10AE10CHECK ABSCM MOTOR DRIVE TERMI-
NAL.
1) Measure voltage between ABSCM connector terminals.
2) Operate the check sequence.
: Connector & terminals
(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 step10AE11.
: Replace ABSCM.
239
4-4cBRAKES [ABS 5.3 TYPE]
10. Diagnostics Chart with Select Monitor

B4M0887A
10AF1CHECK CONTACT POINT OF MOTOR
RELAY.
1) Turn ignition switch to OFF.
2) Remove motor relay from relay box.
3) Connect battery to motor relay terminals No. 85 and No.
86.
4) Measure resistance between motor relay terminals.
: Terminals
No. 30—No. 87
Is resistance less than 0.5Ω?
: Go to next step.
: Replace motor relay.
B4M0888A
5) Disconnect battery from motor relay terminals.
6) Measure resistance between motor relay terminals.
: Terminals
No. 30—No. 87
Is resistance more than 1 MΩ?
: Go to step10AF2.
: Replace motor relay.
B4M0890B
10AF2CHECK INPUT VOLTAGE OF RELAY
BOX.
1) Disconnect connector (F8) from relay box.
2) Measure voltage between relay box connector and
chassis ground.
: Connector & terminal
(F8) No. 2 (+)—Chassis ground ()
Is voltage 10—13 V?
: Go to step10AF3.
: Repair harness connector between battery and
relay box. Check fuse SBF6.
243
4-4cBRAKES [ABS 5.3 TYPE]
10. Diagnostics Chart with Select Monitor

B4M0982
AI: 56 G SENSOR +B
—BATTERY SHORT OF G SENSOR—
DIAGNOSIS:

Faulty G sensor output voltage
TROUBLE SYMPTOM:

ABS does not operate.
10AI1.Check output of G sensor using select
monitor.
10AI2.Check battery short of harness.
10AI3.Check ABSCM.
WIRING DIAGRAM:
B4M1050


258
4-4cBRAKES [ABS 5.3 TYPE]
10. Diagnostics Chart with Select Monitor

B4M0927
10AI1CHECK OUTPUT OF G SENSOR USING
SELECT MONITOR.
1) Press
F,
1and
0on the select monitor.
2) Read the select monitor display.
: Is the indicated reading 2.3±0.2 V when the
G sensor is in horizontal position?
: Replace ABSCM.
: Go to step10AI2.
B4M0914A
10AI2
CHECK BATTERY SHORT OF HARNESS.
1) Turn ignition switch to OFF.
2) Remove console box.
3) Disconnect connector from G sensor.
4) Disconnect connector from ABSCM.
5) Turn ignition switch to ON.
6) Measure voltage between ABSCM connector and chas-
sis ground.
: Connector & terminal
(F49) No. 7 (+)—Chassis ground ()
Is voltage 0 V?
: Go to next step.
: Repair harness between G sensor and ABSCM.
7) Turn ignition switch to OFF.
8) Measure voltage between ABSCM connector and chas-
sis ground.
: Connector & terminal
(F49) No. 7 (+)—Chassis ground ()
Is voltage 0 V?
: Go to step10AI3.
: Repair harness between G sensor and ABSCM.
10AI3
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.
259
4-4cBRAKES [ABS 5.3 TYPE]
10. Diagnostics Chart with Select Monitor