check engine SUBARU LEGACY 1995 Service Manual PDF

G4M0462
3. CHECKING THE HYDRAULIC UNIT WITH BRAKE
TESTER
1) In the case of AWD vehicles, install a spare fuse with
the FWD connector in the engine compartment to simulate
FWD vehicles.
B4M0082A
2) Connect diagnosis terminals to 3 terminals (K) and 6
terminals (L) of the diagnosis connector beside driver seat
heater unit.
G4M0464
3) Set the front wheels or rear wheels on the brake tester
and set the select lever’s position at“neutral”.
4) Operate the brake tester.
5) Perform sequence control.
(1) Turn ignition switch ON.
(2) The ABS warning light comes on.
(3) Depress the brake pedal within 0.5 seconds after
the warning light goes out so that the brake tester reg-
isters a pressure equal to the initial value.
CAUTION:
Do not depress the clutch pedal.
NOTE:
The engine must not be operating.
6) Hydraulic unit begins to work; and check the following
working sequence.
(1) The left front wheel performs decompression,
holding, and compression in sequence, and subse-
quently the right front wheel repeats the cycle.
(2) Simultaneously both right and left rear wheel per-
form decompression, holding, and compression in
sequence.
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4-4SERVICE PROCEDURE
15. Hydraulic Unit for ABS System

7) Read values indicated on the brake tester and check if
the fluctuation of values, when decompressed and
compressed, meet the standard values.
Initial value When decompressed When compressed
Front wheel 1,961 N (200 kg, 441 lb) 245 N (25 kg, 55 lb) 1,961 N (200 kg, 441 lb)
Rear wheel 686 N (70 kg, 154 lb) 245 N (25 kg, 55 lb) 686 N (70 kg, 154 lb)

In case of hydraulic unit plunger piston malfunction:
Initial value When decompressed When compressed
Rear right wheel 686 N (70 kg, 154 lb) 245 N (25 kg, 55 lb) 686 N (70 kg, 154 lb)
Rear left wheel 686 N (70 kg, 154 lb) 686 N (70 kg, 154 lb) 686 N (70 kg, 154 lb)
8) After checking, also check if any irregular brake pedal
tightness is felt.
9) In case of AWD vehicles, remove the spare fuse from
the FWD connector in the engine compartment to return to
the original AWD state.
C: SEQUENCE CONTROL
Under the sequence control, after the hydraulic unit sole-
noid valve is driven, the operation of the hydraulic unit can
be checked by means of the brake tester or pressure
gauge.
B4M0082A
1. OPERATIONAL GUIDELINES OF THE SEQUENCE
CONTROL
1) Connect diagnosis terminals to 3 terminals (K) and 6
terminals (L) of the diagnosis connector beside driver seat
heater unit.
2) Set the speed of all wheels at 4 km/h (2 MPH) or less.
3) Within 0.5 seconds after the ABS warning lamp goes
out, immediately after the ignition switch is turned to on,
depress the brake pedal and hold.
CAUTION:
Do not depress the clutch pedal.
NOTE:

When the ignition switch is set to on, the brake pedal
must not be depressed.

Engine must not operate.
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4-4SERVICE PROCEDURE
15. Hydraulic Unit for ABS System

G4M0436
16) Check the pedal stroke.
While the engine is idling, depress the brake pedal with a
490 N (50 kg, 110 lb) load and measure the distance
between the brake pedal and steering wheel. With the
brake pedal released, measure the distance between the
pedal and steering wheel again. The difference between
the two measurements must be less than specified.
Specified pedal stroke:
With TCS
95 mm (3.74 in)
When depressing brake pedal with a 490 N (50 kg,
110 lb) load.
If the distance is more than specifications, there is a
possibility that air is in the brake line. Bleed air from the
brake line.
17) Turn ignition switch OFF.
18) Disconnect select monitor or diagnosis terminal.
19) Add brake fluid to the required level (MAX. level) of
reserve tank.
20) As a final step, test run the vehicle at low speed and
apply brakes relatively hard 2 to 3 times to ensure that
brakes provide normal braking action on all four wheels
without dragging and uneven braking.
2. CONDITIONS FOR AIR BLEEDING CONTROL
Stop light
switchTCS OFF
switchPump
motorTCS
valveFRO
RLOFLO
RROTCS
operating
indicator
lightABS
warning
lightTCS
warning
light
Air
bleeding
control is
operating.OFF ON ON Close Close Close ON ON ON
ON ON OFF Open Open Close ON ON OFF
ON ON OFF Open Close Open ON OFF ON
ON or OFF OFF OFF Open Close Close ON OFF OFF
Stops tem-
porarily.*——OFF Open Close Close OFF OFF OFF
Prohibited.——OFF Open Close Close OFF ON ON
*: When brake fluid level switch detects brake fluid in LOW level, control operation stops temporarily. After refilling brake fluid, operation
re-starts.
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4-4SERVICE PROCEDURE
19. Air Bleeding (With TCS model)

B4M0628
5) Remove bolts which secure hydraulic unit bracket, and
remove hydraulic unit from engine compartment.
CAUTION:

Hydraulic unit cannot be disassembled. Do not
attempt to loosen bolts and nuts.

Do not drop or bump hydraulic unit.

Do not turn the hydraulic unit upside down or place
it on its side.

Be careful to prevent foreign particles from getting
into hydraulic unit.

Do not pull harness disconnecting harness connec-
tor.
B: INSPECTION
1) Check connected and fixed condition of connector.
2) Check for discontinuity or short circuits.
Condition Terminal number Standard Diagram Terminal location
Valve relayTurning off
electricity.A—B90Ω
B4M0629A
B4M0630
C—F0Ω
C—E
Turning on
electricity between
A and B.
(DC 12 V)C—F
C—E0Ω
Motor relayTurning off
electricity.a—b* 57Ω
B4M0631AB4M0632
c—d
Turning on
electricity between
a and b.
(DC 12 V)c—d0Ω
*: Attach circuit tester positive probe to terminal“a”and its negative probe to terminal“b”and measure the circuit resistance.
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4-4SERVICE PROCEDURE
20. Hydraulic Unit for ABS/TCS System

D: ABS SEQUENCE CONTROL
1) Under the ABS sequence control, after the hydraulic
unit solenoid valve is driven, the operation of the hydraulic
unit can be checked by means of the brake tester or pres-
sure gauge.
2) ABS sequence control can be started by diagnosis con-
nector or select monitor.
B4M0082C
1. OPERATIONAL GUIDELINES OF THE ABS
SEQUENCE CONTROL WITH DIAGNOSIS
CONNECTOR
1) Connect diagnosis terminals to terminal No. 4 of the
diagnosis connector beside driver’s seat heater unit.
2) Ignition switch is turned to ON.
3) Make sure only the start code (code 11) is shown in
normal condition.
NOTE:
When trouble codes are stored in memory, repair the faulty
parts.
4) Set the speed of all wheels at 10 km/h (6 MPH) or less.
5) Turn ignition switch OFF.
6) Within 0.5 seconds after the ABS and TCS warning
lights go out, depress the brake pedal and hold it immedi-
ately after engine starts.
NOTE:

When the ignition switch is set to on, the brake pedal
must not be depressed.

Engine must operate.

If brake pedal is not depressed within 0.5 seconds after
ABS and TCS warning lights go out, the trouble code mode
comes on.
7) After completion of ABS sequence control, turn ignition
switch OFF.
2. OPERATIONAL GUIDELINES OF THE ABS
SEQUENCE CONTROL WITH SELECT MONITOR
1) Connect select monitor to data link connector beside
driver’s seat heater unit.
2) Engine starts.
3) Put select monitor to TCS mode.
4) put select monitor to FBI mode. Make sure code 11 is
indicated.
NOTE:
When trouble codes are stored in memory, repair the faulty
parts.
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4-4SERVICE PROCEDURE
20. Hydraulic Unit for ABS/TCS System

F: TCS SEQUENCE CONTROL
1) Under the TCS sequence control, after the hydraulic
unit solenoid valve is driven, the operation of the hydraulic
unit can be checked by means of the brake tester or pres-
sure gauge.
2) TCS sequence control can be started by diagnosis con-
nector or select monitor.
B4M0082C
1. OPERATIONAL GUIDELINES OF THE TCS
SEQUENCE CONTROL WITH DIAGNOSIS
CONNECTOR
1) Connect diagnosis terminals to terminal No. 4 of the
diagnosis connector beside driver seat heater unit.
2) Ignition switch is turned to ON.
3) Make sure only the start code (code 11) is shown in
normal condition.
NOTE:
When trouble codes are stored in memory, repair the faulty
parts.
4) Set the speed of all wheels at 10 km/h (6 MPH) or less.
5) Turn ignition switch OFF.
6) Start engine, and within 0.5 seconds after the ABS
warning light and TCS warning light go out, press TCS OFF
switch. Within 1.0 second thereafter, release and press the
switch again. Then, keep the switch pressed.
NOTE:

When the TCS sequence control is set to on, the brake
pedal must not be depressed.

Engine must operate.

When TCS OFF switch is not depressed within 0.5 sec-
onds after ABS and TCS warning lights turn off, the trouble
code mode comes on.
7) After completion of TCS sequence control, turn ignition
switch OFF.
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4-4SERVICE PROCEDURE
20. Hydraulic Unit for ABS/TCS System

2. OPERATIONAL GUIDELINES OF THE TCS
SEQUENCE CONTROL WITH SELECT MONITOR
1) Connect select monitor to data link connector beside
driver’s seat heater unit.
2) Engine starts.
3) Put select monitor to TCS mode.
4) Put select monitor to FBI mode. Make sure code 11 is
indicated.
NOTE:
When trouble codes are stored in memory, repair the faulty
parts.
B4M0639
5) Press FD2 ENT key.
B4M0624
6) When the message shown in the figure is displayed,
press ENT key.
7) Checked portions will be displayed on select monitor.
B4M0627
8) When TCS sequence control cannot be started (by sys-
tem malfunction, etc.), the message shown in the figure will
be displayed.
NOTE:
Read the trouble codes. Repair faulty parts.
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4-4SERVICE PROCEDURE
20. Hydraulic Unit for ABS/TCS System

G4M0319
2) If it is not in specified value, adjust it by turning adjust-
ing nut on engine side end of clutch cable.
Free play: L
3—4 mm (0.12—0.16 in)
Full stroke: A
25.5—27 mm (1.004—1.063 in)
3) Apply grease to connecting portion of clutch pedal and
clutch cable.


1Lock nut


2Adjusting nut


3Release fork
Lock nut tightening torque:
5.9±1.5 N⋅m (0.60±0.15 kg-m, 4.3±1.1 ft-lb)
G4M0320
3. ACCELERATOR PEDAL
Check pedal stroke and free play by operating accelerator
pedal by hand.
If it is not within specified value, adjust it by turning nut
connecting accelerator cable to throttle body.
Free play at pedal pad: L
1—4 mm (0.04—0.16 in)
Stroke at pedal pad: A
50—55 mm (1.97—2.17 in)


1Accelerator pedal


2Toe board


3Accelerator cable
Accelerator cable lock nut tightening torque:
14±4 N⋅m (1.4±0.4 kg-m, 10.1±2.9 ft-lb)
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4-5SERVICE PROCEDURE
1. Pedal

G4M0596
7. Evacuating and Charging
The following points should be kept in mind when evacu-
ating and charging with a manifold gauge set.
1) Be certain that goggles and gloves are worn.
2) If bulk refrigerant [13.6 kg (30 lb) canister] is used, be
certain to weigh the charge amount carefully, using the
correct equipment, to avoid overcharging the system.
3) The charging procedure described in this section
begins by chargingliquidrefrigerant into the high- pres-
sure side of the systemwith the engine off.The proce-
dure is completed by charging refrigerantvaporinto the
low-pressure side of the system with the engine running.
CAUTION:
Never open the high-pressure manifold valve when the
engine is running.
G4M0597
1. CONNECT THE GAUGE SET
1) Close the high- and low-pressure manifold valves.
2) Attach the low-pressure manifold hose to the low- pres-
sure service port on the vehicle. Check the low- pressure
gauge. If more than 68.6 kPa (0.70 kg/cm
2, 10 psi) is
indicated, discharge the system prior to charging.
3) Attach the high-pressure manifold hose to the high-
pressure service port on the vehicle.
4) Connect the center hose from the manifold to the
vacuum pump.
5) Turn on the vacuum pump.
6) Slowly open the low-pressure manifold valve.
7) When the low-pressure gauge reaches approximately
66.43 kPa (498.3 mmHg, 19.62 inHg), slowly open the
high-pressure manifold valve.
G4M0598
8) Maintain a minimum vacuum level of 100.56 kPa (754.4
mmHg, 29.70 inHg) for a minimum of 15 minutes on a new
system or 30 minutes for an in-service system.
NOTE:
The gauge will read 4 kPa (25 mmHg, 1 inHg) less for
every 304.8 m (1,000 ft) above sea level.
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4-7SERVICE PROCEDURE
7. Evacuating and Charging

G4M0604
4. INITIAL CHARGING THROUGH THE HIGH SIDE
1) Connect a tachometer to the engine.
2)With the engine off, start charging by slowly opening
the high-pressure manifold valve.
NOTE:
The initial charge rate can be increased by immersing the
can in lukewarm [Below 38°C (100°F)] water for a short
time.
G4M0605
5. CHECK THE GAUGE READINGS
When both the high- and low-pressure gauge readings are
about equal, or the HFC-134a source is empty, or the sys-
tem has been filled to specifications, close the high- pres-
sure manifold valve.
6. ADD ADDITIONAL CANS
If the HFC-134a source is exhausted, first close the high-
pressure manifold valve, second, close the can tap valve,
then slowly purge the refrigerant from the service hose by
loosening the fitting at the can tap. Repeat steps 15
through 19 as necessary.
G4M0606
7. COMPLETE CHARGING THROUGH THE LOW SIDE
1) Verify that the high-pressure manifold valve is closed
(should have already been closed).
2) Verify that the low-pressure manifold valve is closed
(should have already been closed).
G4M0607
3) With the A/C switch off and the windows rolled down,
start the engine and run at idle rpm.
4) Set the A/C controls on maximum cool and set the
blower speed on the highest setting.
5) Quickly turn the A/C switch on-off-on-off a few times to
prevent initial compressor damage due to“load shock.”
Finish this operation with the A/C switch in the ON position.
6) Raise engine rpm to approximately 1,500 rpm.
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4-7SERVICE PROCEDURE
7. Evacuating and Charging