1997 SUBARU LEGACY ABS

10L25
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 step10L26.
10L26CHECK ANY OTHER TROUBLE CODES
APPEARANCE.
: Are other trouble codes being output?
: Proceed with the diagnosis corresponding to the
trouble code.
: A temporary noise interference.
11 8
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

B4M0952
M: TROUBLE CODE 29 EITHER. SS SOFT
—ABNORMAL ABS SENSOR SIGNAL (ANY
ONE OF FOUR)—
DIAGNOSIS:

Faulty ABS sensor signal (noise, irregular signal, etc.)

Faulty tone wheel

Wheels turning freely for a long time
TROUBLE SYMPTOM:

ABS does not operate.
WIRING DIAGRAM:
B4M1238
11 9
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

10M1CHECK IF THE WHEELS HAVE TURNED
FREELY FOR A LONG TIME.
: Check if the wheels have been turned freely
for more than one minute, such as when the
vehicle is jacked-up, under full-lock corner-
ing or when tire is not in contact with road
surface.
: The ABS is normal. Erase the trouble code.
NOTE:
When the wheels turn freely for a long time, such as when
the vehicle is towed or jacked-up, or when steering wheel
is continuously turned all the way, this trouble code may
sometimes occur.
: Go to step10M2.
10M2
CHECK TIRE SPECIFICATIONS.
Turn ignition switch to OFF.
: Are the tire specifications correct?
: Go to step10M3.
: Replace tire.
10M3
CHECK WEAR OF TIRE.
: Is the tire worn excessively?
: Replace tire.
: Go to step10M4.
10M4
CHECK TIRE PRESSURE.
: Is the tire pressure correct?
: Go to step10M5.
: Adjust tire pressure.
10M5CHECK INSTALLATION OF ABS SEN-
SOR.
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
: Are the ABS sensor installation bolts tight-
ened securely?
: Go to step10M6.
: Tighten ABS sensor installation bolts securely.
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4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

10M6CHECK INSTALLATION OF TONE
WHEEL.
Tightening torque:
13±3 N⋅m (1.3±0.3 kg-m, 9±2.2 ft-lb)
: Are the tone wheel installation bolts tight-
ened securely?
: Go to step10M7.
: Tighten tone wheel installation bolts securely.
G4M0700
10M7
CHECK ABS SENSOR GAP.
Measure tone wheel to pole piece gap over entire perim-
eter of the wheel.
: Is the gap within the specifications shown
in the following table?
SpecificationsFront wheel Rear wheel
0.9—1.4 mm
(0.035—0.055 in)0.7—1.2 mm
(0.028—0.047 in)
G4M0701
: Go to step10M8.
: Adjust the gap.
NOTE:
Adjust the gap using spacer (Part No. 26755AA000). If
spacers cannot correct the gap, replace worn sensor or
worn tone wheel.
10M8
CHECK OSCILLOSCOPE.
: Is an oscilloscope available?
: Go to step10M9.
: Go to step10M10.
10M9
CHECK ABS SENSOR SIGNAL.
1) Raise all four wheels of ground.
2) Turn ignition switch OFF.
3) Connect the oscilloscope to the connector (F1) or con-
nector (B100) in accordance with trouble code.
4) Turn ignition switch ON.
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4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

B4M1242A
5) Rotate wheels and measure voltage at specified fre-
quency.
NOTE:
When this inspection is completed, the ABSCM&H/U
sometimes stores the trouble code 29.
Connector & terminal
(B100) No. 12 (+)—No. 13 () (Front RH):
(B100) No. 3 (+)—No.4() (Front LH):
(F1) No. 4 (+)—No.5() (Rear RH):
(F1) No. 1 (+)—No.2() (Rear LH):
Specified voltage: 0.12—1 V (When it is 20 Hz.)
: Is oscilloscope pattern smooth, as shown in
figure?
: Go to step8M13.
: Go to step8M10.
10M10CHECK CONTAMINATION OF ABS SEN-
SOR OR TONE WHEEL.
Remove disc rotor from hub.
: Is the ABS sensor pole piece or the tone
wheel contaminated by dirt or other foreign
matter?
: Thoroughly remove dirt or other foreign matter.
: Go to step10M11.
10M11CHECK DAMAGE OF ABS SENSOR OR
TONE WHEEL.
: Are there broken or damaged teeth in the
ABS sensor pole piece or the tone wheel?
: Replace ABS sensor or tone wheel.
: Go to step10M12.
10M12
CHECK HUB RUNOUT.
Measure hub runout.
: Is the runout less than 0.05 mm (0.0020 in)?
: Go to step10M13.
: Repair hub.
122
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

10M13
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 step10M14.
10M14CHECK ANY OTHER TROUBLE CODES
APPEARANCE.
: Are other trouble codes being output?
: Proceed with the diagnosis corresponding to the
trouble code.
: A temporary poor contact.
123
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

B4M0953
N: TROUBLE CODE 31 FR. EV VALVE
—ABNORMAL FRONT RH INLET SOLENOID
VA LV E—
B4M0954
O: TROUBLE CODE 33 FL. EV VALVE
—ABNORMAL FRONT LH INLET SOLENOID
VA LV E—
B4M0955
P: TROUBLE CODE 35 RR. EV VALVE
—ABNORMAL REAR RH INLET SOLENOID
VA LV E—
B4M0956
Q: TROUBLE CODE 37 RL. EV VALVE
—ABNORMAL REAR LH INLET SOLENOID
VA LV E—
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4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

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