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WIRING DIAGRAM:
B4M1048
B4M0858A
8K1
CHECK RESISTANCE OF VALVE RELAY.
1) Turn ignition switch to OFF.
2) Remove valve relay from relay box.
3) Measure resistance between valve relay terminals.
: Terminals
No. 85—No. 86
Is resistance 103±10Ω?
: Go to step8K2.
: Replace valve relay.
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B4M0811A
8K2CHECK CONTACT POINT OF VALVE
RELAY.
1) Connect battery to valve relay terminals No. 85 and No.
86.
2) Measure resistance between valve relay terminals.
: Terminals
No. 30—No. 87
Is resistance less than 0.5Ω?
: Go to next.
: Replace valve relay.
: Terminals
No. 30—No. 87a
Is resistance more than 1 MΩ?
: Go to next step.
: Replace valve relay.
B4M0798A
3) Disconnect battery from valve relay terminals.
4) Measure resistance between valve relay terminals.
: Terminals
No. 30—No. 87
Is resistance more than 1 MΩ?
: Go to next.
: Replace valve relay.
: Terminals
No. 30—No. 87a
Is resistance less than 0.5Ω?
: Go to step8K3.
: Replace valve relay.
B4M0861A
8K3
CHECK SHORT OF VALVE RELAY.
Measure resistance between valve relay terminals.
: Terminals
No. 86—No. 87
No. 86—No. 87a
Is resistance more than 1 MΩ?
: Go to step8K4.
: Replace valve relay.
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B4M0862B
8K4CHECK POWER SUPPLY VOLTAGE AT
VALVE RELAY CONTACT POINT.
1) Disconnect connector (F8) from relay box.
2) Measure voltage between relay box connector and
chassis ground.
: Connector & terminal
(F8) No. 1 (+)—Chassis ground ( )
Is voltage 10—13 V?
: Go to step8K5.
: Repair harness connector between battery and
relay box. Check fuse No. 19.
B4M0863B
8K5CHECK GROUND CIRCUIT OF RELAY
BOX.
1) Disconnect connector (F50) from relay box.
2) Measure resistance between relay box connector and
chassis ground.
: Connector & terminal
(F50) No. 3—Chassis ground
Is resistance less than 0.5Ω?
: Go to step8K6.
: Repair relay box ground harness.
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B4M0864
8K6CHECK BROKEN WIRE AND GROUND
SHORT IN POWER SUPPLY CIRCUIT OF
RELAY BOX.
1) Disconnect connector (ABS1) from hydraulic unit.
2) Connect connector (F8) to relay box.
3) Measure voltage of relay box.
: Connector & terminal
Valve relay installing point No. 87—Chas-
sis ground
Is voltage 10—13 V?
: Go to step8K7.
: Replace relay box. Check fuse No. 19.
B4M0865A
8K7CHECK BROKEN WIRE IN CONTACT
POINT CIRCUIT OF RELAY BOX.
Measure resistance between hydraulic unit connector and
valve relay installing point.
: Connector & terminal
(ABS1) No. 2—Valve relay installing point
No. 30
Is resistance less than 0.5Ω?
: Go to step8K8.
: Replace relay box.
B4M0866A
8K8CHECK GROUND SHORT IN CONTACT
POINT CIRCUIT OF RELAY BOX.
Measure resistance between hydraulic unit connector and
chassis ground.
: Connector & terminal
(ABS1) No. 2—Chassis ground
Is resistance more than 1 MΩ?
: Go to step8K9.
: Replace relay box. Check fuse SBF6.
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B4M0867A
8K9CHECK BATTERY SHORT IN CONTACT
POINT CIRCUIT OF RELAY BOX.
1) Disconnect connector from ABSCM.
2) Turn ignition switch to ON.
3) Measure voltage between hydraulic unit connector and
chassis ground.
: Connector & terminal
(ABS1) No. 2 (+)—Chassis ground ( )
Is voltage 0 V?
: Go to next step.
: Replace relay box. Check fuse No. 19 and SBF6.
4) Turn ignition switch to OFF.
5) Measure voltage between hydraulic unit connector and
chassis ground.
: Connector & terminal
(ABS1) No. 2 (+)—Chassis ground ( )
Is voltage 0 V?
: Go to step8K10.
: Replace relay box. Check fuse No. 19 and SBF6.
B4M0868B
8K10
CHECK DIODE OF RELAY BOX.
Measure resistance between relay box connector and
valve relay installing point.
: Connector & terminal
Valve relay installing point No. 30 (+)—To
(F50) No. 2 ( )
Is resistance more than 1 MΩ?
: Go to step8K11.
: Replace relay box.
B4M0869B
8K11CHECK BROKEN WIRE IN GROUND CIR-
CUIT OF RELAY BOX.
Measure resistance between relay box connector and
valve relay installing point.
: Connector & terminal
To (F50) No. 3—Valve relay installing point
No. 87a
Is resistance less than 0.5Ω?
: Go to step8K12.
: Replace relay box.
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B4M0870B
8K12CHECK BATTERY SHORT IN GROUND
CIRCUIT OF RELAY BOX.
1) Turn ignition switch to ON.
2) Measure voltage between relay box connector and
chassis ground.
: Connector & terminal
To (F50) No. 3 (+)—Chassis ground ( )
Is voltage 0 V?
: Go to next step.
: Replace relay box and check all fuses.
3) Turn ignition switch to OFF.
4) Measure voltage between relay box connector and
chassis ground.
: Connector & terminal
To (F50) No. 3 (+)—Chassis ground ( )
Is voltage 0 V?
: Go to step8K13.
: Replace relay box and check all fuses.
B4M0871B
8K13CHECK BROKEN WIRE IN CONTROL
CIRCUIT OF RELAY BOX.
1) Install valve relay to relay box.
2) Measure resistance between relay box connector termi-
nals.
: Connector & terminal
To (F50) No. 1—No. 5
Is resistance 103±10Ω?
: Go to step8K14.
: Replace relay box.
B4M0872B
8K14CHECK GROUND SHORT IN CONTROL
CIRCUIT OF RELAY BOX.
Measure resistance between relay box connector and
chassis ground.
: Connector & terminal
To (F50) No. 1—Chassis ground
Is resistance more than 1 MΩ?
: Go to step8K15.
: Replace relay box and check all fuses.
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B4M0873B
8K15CHECK BATTERY SHORT IN CONTROL
CIRCUIT OF RELAY BOX.
1) Turn ignition switch to ON.
2) Measure voltage between relay box connector and
chassis ground.
: Connector & terminal
To (F50) No. 1 (+)—Chassis ground ( )
Is voltage 0 V?
: Go to next step.
: Replace relay box. Check fuse No. 19 and
SBF45A.
3) Turn ignition switch to OFF.
4) Measure voltage between relay box connector and
chassis ground.
: Connector & terminal
To (F50) No. 1 (+)—Chassis ground ( )
Is voltage 0 V?
: Go to step8K16.
: Replace relay box. Check fuse No. 19 and
SBF45A.
B4M0874A
8K16CHECK BROKEN WIRE IN CONTROL
SYSTEM HARNESS OF VALVE RELAY.
1) Connect connector (F50) to relay box.
2) Measure resistance between ABSCM connector termi-
nals.
: Connector & terminal
(F49) No. 27—No. 47
Is resistance 103±10Ω?
: Go to step8K17.
: Repair harness between ABSCM and relay box.
Check fuse No. 18.
B4M0875A
8K17CHECK GROUND SHORT IN CONTROL
SYSTEM HARNESS OF VALVE RELAY.
Measure resistance between ABSCM connector and chas-
sis ground.
: Connector & terminal
(F49) No. 27—Chassis ground
Is resistance more than 1 MΩ?
: Go to step8K18.
: Repair harness between ABSCM and relay box.
Check fuse No. 18.
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B4M0876A
8K18CHECK BATTERY SHORT IN CONTROL
SYSTEM HARNESS OF VALVE RELAY.
1) Turn ignition switch to ON.
2) Measure voltage between ABSCM connector and chas-
sis ground.
: Connector & terminal
(F49) No. 27 (+)—Chassis ground ( )
Is voltage 0 V?
: Go to next step.
: Repair harness between ABSCM and relay box
and check all fuses.
3) Turn ignition switch to OFF.
4) Measure voltage between ABSCM connector and chas-
sis ground.
: Connector & terminal
(F49) No. 27 (+)—Chassis ground ( )
Is voltage 0 V?
: Go to step8K19.
: Repair harness between ABSCM and relay box
and check all fuses.
B4M0824B
8K19CHECK RESISTANCE OF INLET SOLE-
NOID VALVE.
1) Disconnect connector from hydraulic unit.
2) Measure resistance between hydraulic unit connector
terminals.
: Connector & terminal
To (F9) No. 4—to (ABS1) No. 2
To (F9) No. 1—to (ABS1) No. 2
To (F9) No. 2—to (ABS1) No. 2
To (F9) No. 3—to (ABS1) No. 2
Is resistance 8.5±0.7Ω?
: Go to step8K20.
: Replace hydraulic unit.
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