1997 SUBARU LEGACY light

B4M0532
AA: TROUBLE CODE 58
PRESSURE SW
—Faulty pressure switch—
DIAGNOSIS:

Faulty pressure

Faulty stop light switch

Faulty ABS/TCS control module

Faulty harness/connector
TROUBLE SYMPTOM:

TCS does not operate.
NOTE:
Check using the select monitor.
Operate the function FA0 in select monitor TCS mode. The
stop and brake switches can be checked by B1 LED
ON/OFF. If system is normal, LED comes on when
depressing brake pedal, and goes off when not depressing.
If so, skip check steps 5 through 8.
1. Check contact point of pressure switch.

OK
Not OK
Replace hydraulic unit.
2. Check body short of pressure switch.

OK
Not OK
Replace hydraulic unit.
3. Check harness between pressure switch and
ABS/TCS control module.

OK
Not OK
Repair harness/connector.
4. Check body short of pressure switch harness.

OK
Not OK
Repair harness.
5. Check contact point of stop light switch.

OK
Not OK
Replace stroke sensor.
6. Check body short of stop light switch.

OK
Not OK
Replace stroke sensor.
7. Check power supply of stop light switch.

OK
Not OK
Repair harness.
8. Check input voltage of ABS/TCS control mod-
ule.

OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.








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4-4bBRAKES
10. Diagnostic Chart with Select Monitor

12. Phenomena Peculiar to the System
1. WHEN TRAVELING WITH EXTREMELY UNDER
INFLATED TIRES
The TCS is apt to operate (particularly when turning) and,
when it operates, acceleration can become slow*. This
state is not abnormal. Immediately restore the tires to nor-
mal by traveling after releasing the TCS with the TCS OFF
switch.
* Poor acceleration is sometimes caused by the engine
itself. Check whether or not the TCS operating indicator
light (green) comes on to determine that the failure is
caused by the TCS control.
2. WHEN THE T TIRES ARE FITTED
The TCS is apt to operate (particularly when turning) and,
when it operates, acceleration can become slow. This state
is not abnormal. Immediately restore the tires to normal by
traveling after releasing the TCS with the TCS OFF switch.
3. WHEN OPERATING THE TCS CONTINUOUSLY ON
A SLOPE IMPOSSIBLE TO CLIMB OR IN STACK
S TAT E
When operating the TCS for a long time, it can be auto-
matically turned off (the OFF indicator light will come on),
stopping braking. This state is not abnormal. It automati-
cally resets by stopping and leaving the vehicle.
4. WHEN HEAVY LOAD IS PLACED ON THE BRAKES
If service brakes are used too often when descending a
long slope, heavy load can be placed on the brakes. To
prevent this problem, the TCS is automatically turned off
(the OFF indicator light will come on). This state is not
abnormal. Stop the vehicle and leave it in the same way as
step 3, it automatically resets.
5. KICKBACK TO THE BRAKE PEDAL WHEN THE
ABS IS OPERATING
Compared with ABS of the AWD model system, pedal kick-
back with large amplitude of vibration and long cycle can
be felt. This is caused by the difference in system configu-
ration and, therefore, not abnormal. If you receive an
inquiry from your clients, fully explain this point.
128
4-4bBRAKES
12. Phenomena Peculiar to the System

B: ELECTRICAL INSPECTION
1. WARNING LIGHT ILLUMINATION PATTERN
B4M0781A
1) When the ABS warning light does not illuminate in
accordance with this illumination pattern, there must be an
electrical malfunction.
2) When the ABS warning light remains constantly OFF,
refer to“7. Diagnostics Chart for ABS Warning Light Circuit
and Diagnosis Circuit Failure”in this section, for repair.

NOTE:
Even though the ABS warning light does not go out 1.5
seconds after it illuminates, the ABS system operates nor-
mally when the warning light goes out while driving at
approximately 12 km/h (7 MPH). However, the Anti-lock
brakes do not work while the ABS warning light is illumi-
nated.
3
4-4cBRAKES [ABS 5.3 TYPE]
2. Pre-inspection

3. Electrical Components Location
B4M0782A
1Hydraulic control unit (H/U)

2Proportioning valve

3ABS control module (ABSCM)

4Diagnosis connector

5ABS warning light

6Data link connector (for Subaru select monitor)

7Transmission control module (only AT vehicle)
8Tone wheel

9ABS sensor

10Wheel cylinder

11G sensor (only AWD vehicle)

12Brake switch

13Master cylinder

14Relay box
4
4-4cBRAKES [ABS 5.3 TYPE]
3. Electrical Components Location

4. Schematic
B4M0787A
1Hydraulic control unit (H/U)

2Front left inlet solenoid valve

3Front left outlet solenoid valve

4Front right inlet solenoid valve

5Front right outlet solenoid valve

6Rear left inlet solenoid valve

7Rear left outlet solenoid valve

8Rear right inlet solenoid valve

9Rear right outlet solenoid valve

10Motor

11Transmission control module (only AT model)

12ABS warning light

13Motor relay
14Valve relay

15Relay box

16Data link connector

17Diagnosis connector

18Stop light switch

19Stop light

20G sensor (only AWD model)

21Front left ABS sensor

22Front right ABS sensor

23Rear left ABS sensor

24Rear right ABS sensor

25ABS control module (ABSCM)
6
4-4cBRAKES [ABS 5.3 TYPE]
4. Schematic

Contents Terminal No.Input/Output signal
Measured value and measuring conditions
ABS sensor
(Wheel
speed
sensor)Front left wheel 49—19
0.12—1V
(When it is 20 Hz.) Front right wheel 14—15
Rear left wheel 16—17
Rear right wheel 18—46
Hydraulic
control unitSolenoid
valveFront left outlet 51—1
10—13 V when the valve is OFF and
less than 1.5 V when the valve is ON. Front right outlet 3—1
Rear left outlet 4—1
Rear right outlet 50—1
Front left inlet 24—1
Front right inlet 30—1
Rear left inlet 31—1
Rear right inlet 23—1
Relay boxValve relay power supply 27—110—13 V when ignition switch is ON.
Valve relay coil 47—1 Less than 1.5 V when ignition switch is ON.
Motor relay coil 22—1More than 10 V when the ABS control does not operate still
and less than 1.5 V when ABS operates.
Motor monitoring 10—1Less than 1.5 V when the ABS control does not operate still
and more than 10 V when ABS operates.
G sensor
(AWD
model only)power supply 8—45 4.75—5.25 V
ground 45—
output 7—45 2.3±0.2 V when vehicle is in horizontal position.
Stop light switch 36—1Less than 1.5 V when the stop light is OFF and more than
4.5 V when the stop light is ON.
ABS warning light 54—1Less than 1.5 V during 1.5 seconds when ignition switch is
ON, and 10—14 V after 1.5 seconds.
AT ABS signal
(AT model only)12—1Less than 1.5 V when the ABS control does not operate still
and more than 5.5 V when ABS operates.
ABS operation signal monitor 39—1Less than 1.5 V when the ABS control does not operate still
and more than 5.5 V when ABS operates.
Select
monitorData is received. 11—1 Less than 1.5 V when no data is received.
Data is sent. 38—1 4.75—5.25 V when no data is sent.
Diagnosis
connectorTerminal No. 3 5—110—14 V when ignition switch is ON.
Terminal No. 6 13—110—14 V when ignition switch is ON.
Power supply 28—110—14 V when ignition switch is ON.
Grounding line 1—
Grounding line 55—
8
4-4cBRAKES [ABS 5.3 TYPE]
5. Control Module I/O Signal

6. Diagnostics Chart for On-board
Diagnosis System
A: BASIC DIAGNOSTICS PROCEDURE
TROUBLE OCCURS.
Is Select Monitor available?
No
Ye s
10. Diagnostic Chart with Select
Monitor
Ask the customer when and how the
trouble occurred using interview
check list.
PRE-INSPECTION

CALLING UP A TROUBLE CODE.
No trouble code is readable.

Inspection using Diagnostic Chart for
Warning Light Failure.

Record all trouble codes.
Trouble codes
are issued.
Only the start code is issued.
Inspection using General Diagnostics
Chart

Perform diagnostics in accordance with trouble code.

Trouble code
designated.

Repair.
Clear memory.

INSPECTION MODE

CALLING UP A TROUBLE CODE.

Only the start code is issued.
CONFIRMATION TEST
END
NOTE:

To check harness for broken wires or short circuits,
shake it while holding it or the connector.

When ABS warning light illuminates, read and record
trouble code indicated by ABS warning light.












10
4-4cBRAKES [ABS 5.3 TYPE]
6. Diagnostics Chart for On-board Diagnosis System

B: CHECK LIST FOR INTERVIEW
Check the following items about the vehicle’s state.
1. THE STATE OF THE WARNING LIGHTS
a. ABS warning light

1Is always on.2Sometimes comes on.3Comes on only once.4Does not come on.
When/how long does it come on?
Ignition key
position
1Lock2Acc3On (before starting engine)4Start5On after starting (Engine: run)
6On after starting (Engine: stop)
Timing
1Immediately after ignition is on.2Immediately after ignition starts.
3When advancing (Speedmiles/h,miles/h)4While traveling at a constant speed (Speedmiles/h)
5When decelerating (Speedmiles/h,miles/h)
6When turning (To right, to left, steering angledeg., steering timesec)
7When moving other electrical parts (Part name:, Operating condition)
2. SYMPTOMS
ABS operating
condition1Performs no work.2Operates only when abruptly applying brakes. (Conditions: vehicle speedmiles/h, how to step
on brake pedal)
3Operating time (sec., etc.)4Operating noise (Produced/Not produced)
5What kind of noise? (Knock, gong gong, bong, buzz, gong gong buzz, etc.)
6Reaction force of brake pedal (Stick, pressed down once with a clunk, pressed and released, etc.)
Behavior of
vehicle
1Directional stability cannot be obtained or steering arm refuses to work when applying brakes (vehicle turns to right, turns
to left, spins, etc.).
2Directional stability cannot be obtained or steering arm refuses to work when accelerating (vehicle turns to right, turns to
left, spins, etc.).
3Brakes are out of order (braking distance is long, brakes lock or drag, pedal stroke is long, pedal sticks, etc.).
4Poor acceleration (fails to accelerate, engine stalls, etc.).
5Vibration, abnormal noise (operating noise is loud, noise is produced during operation from the front of vehicle (right, left)
(tones:), noise is produced during operation from the rear of vehicle (tones:, others)
6Other phenomena (concrete symptoms)
3. CONDITIONS UNDER WHICH TROUBLE OCCURS
Environment1Weather (fine, cloudy, rain, snow, etc.)
2Ambient temperature (°C/°F)
3Road (urban area, suburbs, highway, general road, ascending slope, descending slope, paved road, gravel road, muddy
road, sandy place, etc.)
4Road surface (dry, wet, new-fallen snow, compressed snow, frozen slope, etc.)
Conditions
1Brakes (decelerationg, continuous/intermittent)2Accelerator (accelerationg, continuous/intermittent)
3Travel speed (miles, advancing, accelerating, reducing speed, low speed, turning, etc.)
4Condition of tire of each wheel (air pressure, degree of wear, whether or not genuine parts are used, whether
or not chain is passed around tires, whether or not T tire is used.) others ()
5Condition of suspension alignment ()
6Loading state ()
4. REPAIRED PARTS ARE USED OR NOT
11
4-4cBRAKES [ABS 5.3 TYPE]
6. Diagnostics Chart for On-board Diagnosis System