1996 SUBARU LEGACY brake

B4M0806B
B4M1036A
8C2
CHECK RESISTANCE OF ABS SENSOR.
1) Turn ignition switch OFF.
2) Disconnect connector from ABS sensor.
3) Measure resistance between ABS sensor connector ter-
minals.
: Trouble code/Connector & terminal
22/to (B6) No. 1—No. 2
24/to (B15) No. 1—No. 2
26/to (P8) No. 1—No. 2
28/to (P9) No. 1—No. 2
Is resistance 0.8—1.2 kΩ?
: Go to step8C3.
: Replace ABS sensor.
B4M0818B
B4M1042A
8C3CHECK GROUND SHORT OF ABS SEN-
SOR.
Measure resistance between ABS sensor and chassis
ground.
: Trouble code/Connector & terminal
22/to (B6) No. 1—Chassis ground
24/to (B15) No. 1—Chassis ground
26/to (P8) No. 1—Chassis ground
28/to (P9) No. 1—Chassis ground
Is resistance more than 1 MΩ?
: Go to step8C4.
: Replace ABS sensor.
38
4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

B4M0809A
8C4CHECK HARNESS CONNECTOR
BETWEEN ABSCM AND ABS SENSOR.
1) Connect connector to ABS sensor.
2) Disconnect connector from ABS control module.
3) Measure resistance at ABSCM connector terminals.
: Trouble code/Connector & terminal
22/(F49) No. 14—No. 15
24/(F49) No. 49—No. 19
26/(F49) No. 18—No. 46
28/(F49) No. 16—No. 17
Is resistance 0.8—1.2 kΩ?
: Go to step8C5.
: Repair harness connector between ABSCM and
ABS sensor.
B4M0820A
8C5
CHECK GROUND SHORT OF HARNESS.
Measure resistance between ABSCM connector and chas-
sis ground.
: Trouble code/Connector & terminal
22/(F49) No. 14—Chassis ground
24/(F49) No. 49—Chassis ground
26/(F49) No. 18—Chassis ground
28/(F49) No. 16—Chassis ground
Is resistance more than 1 MΩ?
: Go to step8C6.
: Repair harness connector between ABSCM and
ABS sensor.
39
4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

B4M0814A
8C6
CHECK GROUND CIRCUIT OF ABSCM.
Measure resistance between ABSCM and chassis ground.
: Connector & terminal
(F49) No. 1—GND
(F49) No. 55—GND
Is resistance less than 0.5Ω?
: Go to step8C7.
: Repair ABSCM ground harness.
8C7CHECK POOR CONTACT IN CONNEC-
TOR BETWEEN ABSCM AND ABS SEN-
SOR.
: Is there poor contact in connectors between
ABSCM and ABS sensor?
: Repair connector.
: Go to step8C8.
8C8
CHECK SOURCES OF SIGNAL NOISE.
: Is the car telephone or the wireless trans-
mitter properly installed?
: Go to next.
: Properly install the car telephone or the wireless
transmitter.
: Are noise sources (such as an antenna)
installed near the sensor harness?
: Install the noise sources apart from the sensor
harness.
: Go to step8C9.
40
4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

B4M1038A
8C9
CHECK SHIELD CIRCUIT.
1) Connect all connectors.
2) Measure resistance between shield connector and
chassis ground.
: Trouble code/Connector & terminal
22/(B100) No. 11—Chassis ground
24/(B100) No. 2—Chassis ground
26/(P1) No. 8—Chassis ground
28/(P1) No. 3—Chassis ground
Is resistance less than 0.5Ω?
: Go to step8C10.
: Repair shield harness.
8C10
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 noise interference.
41
4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

D: TROUBLE CODE 29
—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.
8D1.Check if the wheels have turned freely for a
long time.
8D2.Check tire.
8D3.Check ABS sensor mechanical trouble.
8D4.Check ABSCM.



42
4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

WIRING DIAGRAM:
B4M1035
8D1CHECK 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 step8D2.
43
4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

8D2
CHECK TIRE.
: Are the tire specifications correct?
: Go to next.
: Replace tire.
: Is the tire worn excessively?
: Replace tire.
: Go to next.
: Is the tire pressure correct?
: Go to step8D3.
: Adjust tire pressure.
8D3CHECK ABS SENSOR MECHANICAL
TROUBLE.
: 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 next.
: Tighten ABS sensor installation bolts securely.
: 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 next step.
: Tighten tone wheel installation bolts securely.
G4M0700
1) Measure tone wheel to pole piece gap over entire
perimeter 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)
44
4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code

G4M0701
: Go to next.
: 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.
: Is an oscilloscope available?
: Go to next step.
: Go to step 10).
2) Raise all four wheels of ground.
3) Turn ignition switch OFF.
4) Disconnect connector from ABS control module.
5) Disconnect connector cover from connector.

6) Connect connector to ABS control module.
7) Connect the oscilloscope to the ABS control module
connector.
8) Turn ignition switch ON.
B4M0816A
9) Rotate wheels and measure voltage at specified fre-
quency.
NOTE:
When this inspection is completed, the ABS control mod-
ule sometimes stores the trouble code 29.
TROUBLE CODE / Connector & terminal:
(F49) No. 14 (+)—No. 15 () (Front RH)
(F49) No. 49 (+)—No. 19 () (Front LH)
(F49) No. 18 (+)—No. 46 () (Rear RH)
(F49) No. 16 (+)—No. 17 () (Rear LH)
Specified voltage: 0.12—1 V (When it is 20 Hz.)
: Is oscilloscope pattern smooth, as shown in
figure?
: Go to step8D4.
: Go to next step.
45
4-4cBRAKES [ABS 5.3 TYPE]
8. Diagnostics Chart with Trouble Code