SUBARU LEGACY 1997 Service Repair Manual

DIAGNOSIS:

Faulty harness/connector

Faulty inlet solenoid valve
TROUBLE SYMPTOM:

ABS does not operate.
WIRING DIAGRAM:
B4M1245
125
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

B4M1234A
10Q1CHECK INPUT VOLTAGE OF
ABSCM&H/U.
1) Turn ignition switch to OFF.
2) Disconnect connector from ABSCM&H/U.
3) Run the engine at idle.
4) Measure voltage between ABSCM&H/U connector and
chassis ground.
Connector & terminal
(F49) No. 1 (+)—Chassis ground ():
: Is the voltage between 10 V and 15 V?
: Go to step10Q2.
: Repair harness connector between battery, igni-
tion switch and ABSCM&H/U.
B4M1243A
10Q2CHECK GROUND CIRCUIT OF
ABSCM&H/U.
1) Turn ignition switch to OFF.
2) Measure resistance between ABSCM&H/U connector
and chassis ground.
Connector & terminal
(F49) No. 23—Chassis ground:
: Is the resistance less than 0.5Ω?
: Go to step10Q3.
: Repair ABSCM&H/U ground harness.
10Q3CHECK POOR CONTACT IN CONNEC-
TORS.
: Is there poor contact in connectors between
generator, battery and ABSCM&H/U? to FOREWORD [T3C1].>
: Repair connector.
: Go to step10Q4.
126
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

10Q4
CHECK ABSCM&H/U.
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&H/U.
: Go to step10Q5.
10Q5CHECK ANY OTHER TROUBLE CODES
APPEARANCE.
: Are other trouble codes being output?
: Proceed with the diagnosis corresponding to the
trouble code.
: A temporary poor contact.
127
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

B4M0958
R: TROUBLE CODE 32 FR. AV VALVE
—ABNORMAL FRONT RH OUTLET
SOLENOID VALVE—
B4M0959
S: TROUBLE CODE 34 FL. AV VALVE
—ABNORMAL FRONT LH OUTLET
SOLENOID VALVE—
B4M0960
T: TROUBLE CODE 36 RR. AV VALVE
—ABNORMAL REAR RH OUTLET SOLENOID
VA LV E—
B4M0961
U: TROUBLE CODE 38 RL. AV VALVE
—ABNORMAL REAR LH OUTLET SOLENOID
VA LV E—
128
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

DIAGNOSIS:

Faulty harness/connector

Faulty outlet solenoid valve
TROUBLE SYMPTOM:

ABS does not operate.
WIRING DIAGRAM:
B4M1245
129
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

B4M1234A
10U1CHECK INPUT VOLTAGE OF
ABSCM&H/U.
1) Turn ignition switch to OFF.
2) Disconnect connector from ABSCM&H/U.
3) Run the engine at idle.
4) Measure voltage between ABSCM&H/U connector and
chassis ground.
Connector & terminal
(F49) No. 1 (+)—Chassis ground ():
: Is the voltage between 10 V and 15 V?
: Go to step10U2.
: Repair harness connector between battery, igni-
tion switch and ABSCM&H/U.
B4M1243A
10U2CHECK GROUND CIRCUIT OF
ABSCM&H/U.
1) Turn ignition switch to OFF.
2) Measure resistance between ABSCM&H/U connector
and chassis ground.
Connector & terminal
(F49) No. 23—Chassis ground:
: Is the resistance less than 0.5Ω?
: Go to step10U3.
: Repair ABSCM&H/U ground harness.
10U3CHECK POOR CONTACT IN CONNEC-
TORS.
: Is there poor contact in connectors between
generator, battery and ABSCM&H/U? to FOREWORD [T3C1].>
: Repair connector.
: Go to step10U4.
130
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

10U4
CHECK ABSCM&H/U.
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&H/U.
: Go to step10U5.
10U5CHECK ANY OTHER TROUBLE CODES
APPEARANCE.
: Are other trouble codes being output?
: Proceed with the diagnosis corresponding to the
trouble code.
: A temporary poor contact.
131
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

B4M0962
V: TROUBLE CODE 41 ECU
—ABNORMAL ABS CONTROL MODULE—
DIAGNOSIS:

Faulty ABSCM&H/U
TROUBLE SYMPTOM:

ABS does not operate.
WIRING DIAGRAM:
B4M1246
132
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

B4M1243A
10V1CHECK GROUND CIRCUIT OF
ABSCM&H/U.
1) Turn ignition switch to OFF.
2) Disconnect connector from ABSCM&H/U.
3) Measure resistance between ABSCM&H/U and chassis
ground.
Connector & terminal
(F49) No. 23—Chassis ground:
: Is the resistance less than 0.5Ω?
: Go to step10V2.
: Repair ABSCM&H/U ground harness.
10V2CHECK POOR CONTACT IN CONNEC-
TORS.
: Is there poor contact in connectors between
battery, ignition switch and ABSCM&H/U?

: Repair connector.
: Go to step10V3.
10V3
CHECK SOURCES OF SIGNAL NOISE.
: Is the car telephone or the wireless trans-
mitter properly installed?
: Go to step10V4.
: Properly install the car telephone or the wireless
transmitter.
10V4
CHECK SOURCES OF SIGNAL NOISE.
: Are noise sources (such as an antenna)
installed near the sensor harness?
: Install the noise sources apart from the sensor
harness.
: Go to step10V5.
10V5
CHECK ABSCM&H/U.
1) Turn ignition switch to OFF.
2) Connect all connectors.
3) Erase the memory.
4) Perform inspection mode.
5) Read out the trouble code.
: Is the same trouble code as in the current
diagnosis still being output?
: Replace ABSCM&H/U.
: Go to step10V6.
133
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

10V6CHECK ANY OTHER TROUBLE CODES
APPEARANCE.
: Are other trouble codes being output?
: Proceed with the diagnosis corresponding to the
trouble code.
: A temporary poor contact.
134
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor