SUBARU LEGACY 1997 Service Repair Manual
Page 3051 of 3342
B4M0927
10AI1CHECK OUTPUT OF G SENSOR USING
SELECT MONITOR.
1) Press [F], [1] and [0] on 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?
: Go to step10AI2.
: Go to step10AI6.
10AI2CHECK POOR CONTACT IN CONNEC-
TORS.
Turn ignition switch to OFF.
: Is there poor contact in connector between
ABSCM&H/U and G sensor? <Ref. to FORE-
WORD [T3C1].>
: Repair connector.
: Go to step10AI3.
10AI3
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 step10AI4.
10AI4CHECK ANY OTHER TROUBLE CODES
APPEARANCE.
: Are other trouble codes being output?
: Proceed with the diagnosis corresponding to the
trouble code.
: A temporary poor contact.
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10. Diagnostics Chart with Select Monitor
Page 3052 of 3342
B4M1261A
10AI5CHECK OPEN CIRCUIT IN G SENSOR
OUTPUT HARNESS AND GROUND HAR-
NESS.
1) Turn ignition switch to OFF.
2) Disconnect connector from ABSCM&H/U.
3) Measure resistance between ABSCM&H/U connector
terminals.
Connector & terminal
(F49) No. 30—No. 28:
: Is the resistance between 4.3 and 4.9 kΩ?
: Go to step10AI6.
: Repair harness/connector between G sensor and
ABSCM&H/U.
B4M1264A
10AI6
CHECK GROUND SHORT OF HARNESS.
Measure resistance between ABSCM&H/U connector and
chassis ground.
Connector & terminal
(F49) No. 28—Chassis ground:
: Is the resistance more than 1 MΩ?
: Go to step10AI7.
: Repair harness between G sensor and
ABSCM&H/U.
Replace ABSCM&H/U.
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10. Diagnostics Chart with Select Monitor
Page 3053 of 3342
B4M0915
10AI7
CHECK G SENSOR.
1) Remove console box.
2) Remove G sensor from vehicle.
3) Connect connector to G sensor.
4) Connect connector to ABSCM&H/U.
5) Turn ignition switch to ON.
6) Measure voltage between G sensor connector termi-
nals.
Connector & terminal
(P11) No. 2 (+)—No.1( ):
: Is the voltage between 2.1 and 2.5 V when G
sensor is horizontal?
: Go to step10AI8.
: Replace G sensor.
B4M0917A
10AI8
CHECK G SENSOR.
Measure voltage between G sensor connector terminals.
Connector & terminal
(R70) No. 2 (+)—No.1( ):
: Is the voltage between 3.7 and 4.1 V when G
sensor is inclined forwards to 90°?
: Go to step10AI9.
: Replace G sensor.
B4M0918A
10AI9
CHECK G SENSOR.
Measure voltage between G sensor connector terminals.
Connector & terminal
(R70) No. 2 (+)—No.1( ):
: Is the voltage between 0.5 and 0.9 V when G
sensor is inclined backwards to 90°?
: Go to step10AI10.
: Replace G sensor.
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10. Diagnostics Chart with Select Monitor
Page 3054 of 3342
10AI10
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 step10AI11.
10AI11CHECK ANY OTHER TROUBLE CODES
APPEARANCE.
: Are other trouble codes being output?
: Proceed with the diagnosis corresponding to the
trouble code.
: A temporary poor contact.
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10. Diagnostics Chart with Select Monitor
Page 3055 of 3342
B4M0813
AJ: TROUBLE CODE 56 G SENSOR STICK
—G SENSOR OUTPUT IS STUCK—
DIAGNOSIS:
Faulty G sensor output voltage
TROUBLE SYMPTOM:
ABS does not operate.
WIRING DIAGRAM:
H 4 M 1111
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10. Diagnostics Chart with Select Monitor
Page 3056 of 3342
10AJ1CHECK ALL FOUR WHEELS FOR FREE
TURNING.
: Have the wheels been turned freely such as
when the vehicle is lifted up, or operated on
a rolling road?
: The ABS is normal. Erase the trouble code.
: Go to step10AJ2.
B4M0927
10AJ2CHECK OUTPUT OF G SENSOR USING
SELECT MONITOR.
1) Press [F], [1] and [0] on the select monitor.
2) Read the select monitor display.
: Is the indicated reading between 2.1 and 2.5
V when the vehicle is in horizontal position?
: Go to step10AJ3.
: Go to step10AJ8.
B4M0917A
10AJ3CHECK OUTPUT OF G SENSOR USING
SELECT MONITOR.
1) Turn ignition switch to OFF.
2) Remove console box.
3) Remove G sensor from vehicle. (Do not disconnect
connector.)
4) Turn ignition switch to ON.
5) Press [F], [1] and [0] on the select monitor.
6) Read the select monitor display.
: Is the indicated reading between 3.7 and 4.1
V when G sensor is inclined forwards to
90°?
: Go to step10AJ4.
: Replace G sensor.
B4M0918A
10AJ4CHECK OUTPUT OF G SENSOR USING
SELECT MONITOR.
Read the select monitor display.
: Is the indicated reading between 0.5 and 0.9
V when G sensor is inclined backwards to
90°?
: Go to step10AJ5.
: Replace G sensor.
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10. Diagnostics Chart with Select Monitor
Page 3057 of 3342
10AJ5CHECK POOR CONTACT IN CONNEC-
TORS.
Turn ignition switch to OFF.
: Is there poor contact in connector between
ABSCM&H/U and G sensor? <Ref. to FORE-
WORD [T3C1].>
: Repair connector.
: Go to step10AJ6.
10AJ6
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 step10AJ7.
10AJ7CHECK ANY OTHER TROUBLE CODES
APPEARANCE.
: Are other trouble codes being output?
: Proceed with the diagnosis corresponding to the
trouble code.
: A temporary poor contact.
B4M1261A
10AJ8CHECK OPEN CIRCUIT IN G SENSOR
OUTPUT HARNESS AND GROUND HAR-
NESS.
1) Turn ignition switch to OFF.
2) Disconnect connector from ABSCM&H/U.
3) Measure resistance between ABSCM&H/U connector
terminals.
Connector & terminal
(F49) No. 30—No. 28:
: Is the resistance between 4.3 and 4.9 kΩ?
: Go to step10AJ9.
: Repair harness/connector between G sensor and
ABSCM&H/U.
181
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10. Diagnostics Chart with Select Monitor
Page 3058 of 3342
B4M0915
10AJ9
CHECK G SENSOR.
1) Remove console box.
2) Remove G sensor from vehicle.
3) Connect connector to G sensor.
4) Connect connector to ABSCM&H/U.
5) Turn ignition switch to ON.
6) Measure voltage between G sensor connector termi-
nals.
Connector & terminal
(P11) No. 2 (+)—No.1( ):
: Is the voltage between 2.1 and 2.5 V when G
sensor is horizontal?
: Go to step10AJ10.
: Replace G sensor.
B4M0917A
10AJ10
CHECK G SENSOR.
Measure voltage between G sensor connector terminals.
Connector & terminal
(P11) No. 2 (+)—No.1( ):
: Is the voltage between 3.7 and 4.1 V when G
sensor is inclined forwards to 90°?
: Go to step10AJ11.
: Replace G sensor.
B4M0918A
10AJ11
CHECK G SENSOR.
Measure voltage between G sensor connector terminals.
Connector & terminal
(P11) No. 2 (+)—No.1( ):
: Is the voltage between 0.5 and 0.9 V when G
sensor is inclined backwards to 90°?
: Go to step10AJ12.
: Replace G sensor.
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10. Diagnostics Chart with Select Monitor
Page 3059 of 3342
10AJ12
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 step10AJ13.
10AJ13CHECK ANY OTHER TROUBLE CODES
APPEARANCE.
: Are other trouble codes being output?
: Proceed with the diagnosis corresponding to the
trouble code.
: A temporary poor contact.
183
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10. Diagnostics Chart with Select Monitor
Page 3060 of 3342
11. General Diagnostics Table
A: SYMPTOMS AND PROBABLE CAUSES
Symptom Probable faulty units/parts
Vehicle instability during brakingVehicle pulls to either side.ABSCM&H/U (solenoid valve)
ABS sensor
Brake (caliper & piston, pads)
Wheel alignment
Tire specifications, tire wear and air pressures
Incorrect wiring or piping connections
Road surface (uneven, camber)
Vehicle spins.ABSCM&H/U (solenoid valve)
ABS sensor
Brake (pads)
Tire specifications, tire wear and air pressures
Incorrect wiring or piping connections
Poor brakingLong braking/stopping distanceABSCM&H/U (solenoid valve)
Brake (pads)
Air in brake line
Tire specifications, tire wear and air pressures
Incorrect wiring or piping connections
Wheel locks.ABSCM&H/U (solenoid valve, motor)
ABS sensor
Incorrect wiring or piping connections
Brake draggingABSCM&H/U (solenoid valve)
ABS sensor
Master cylinder
Brake (caliper & piston)
Parking brake
Axle & wheels
Brake pedal play
Long brake pedal strokeAir in brake line
Brake pedal play
Vehicle pitchingSuspension play or fatigue (reduced damping)
Incorrect wiring or piping connections
Road surface (uneven)
Unstable or uneven brakingABSCM&H/U (solenoid valve)
ABS sensor
Brake (caliper & piston, pads)
Tire specifications, tire wear and air pressures
Incorrect wiring or piping connections
Road surface (uneven)
Vibration and/or noise (while
driving on slippery roads)Excessive pedal vibrationIncorrect wiring or piping connections
Road surface (uneven)
Noise from ABSCM&H/UABSCM&H/U (mount bushing)
ABS sensor
Brake piping
Noise from front of vehicleABSCM & H/U (mount bushing)
ABS sensor
Master cylinder
Brake (caliper & piston, pads, rotor)
Brake piping
Brake booster & check valve
Suspension play or fatigue
Noise from rear of vehicleABS sensor
Brake (caliper & piston, pads, rotor)
Parking brake
Brake piping
Suspension play or fatigue
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11. General Diagnostics Table