SUBARU LEGACY 1996 Service Repair Manual

2. CHECKING THE HYDRAULIC UNIT TCS
OPERATION WITH BRAKE TESTER
1) Prepare for operating TCS sequence control. 4-4 [W20F1] step 1 or 4-4 [W20F2] step 1.>
B4M0638
2) Set the front wheels on the brake tester and set the
select lever’s position at“neutral”.
3) Operate the brake tester.
4) Perform sequence control. [W20F2].>
5) Hydraulic unit begins to work; and check the following
working sequence.
The front left wheel performs compression, holding,
and decompression in sequence, and subsequently the
front right wheel repeats the cycle.
6) Read values indicated on the brake tester and check if
the fluctuation of values, when decompressed and
compressed, meet the standard values.
When compressed When decompressed
Front left wheel 981—1,471 N (100—150 kg, 221—331 lb) 245 N (25 kg, 55 lb) or less
Front right wheel 981—1,471 N (100—150 kg, 221—331 lb) 245 N (25 kg, 55 lb) or less
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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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20. Hydraulic Unit for ABS/TCS System

3. CONDITIONS FOR COMPLETION OF TCS
SEQUENCE CONTROL
When the following conditions develop, the TCS sequence
control stops and ABS and TCS warning lights come on
while the ABS and TCS function will then stop. The brake
system functions as a conventional brake system.
1) When the speed of at least one wheel reaches 10 km/h
(6 MPH).
2) When terminal No. 4 is separated from ground. (When
select monitor is not used.)
3) When the brake pedal is depressed during sequence
control and the braking lamp switch is set to ON.
4) When TCS OFF switch is released. (When select moni-
tor is not used.)
5) After completion of the TCS sequence control.
6) When output signal to break TCS control is emitted from
ECM.
7) When malfunction is detected.
NOTE:
When malfunction has been detected and the TCS
sequence control operation has stopped, the trouble codes
are stored in memory.
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20. Hydraulic Unit for ABS/TCS System

4. CONDITIONS FOR TCS SEQUENCE CONTROL
B4M0642A
NOTE:
When select monitor is used, control operation starts at
point A. It is not required to operate TCS OFF switch for
starting control operation. The patterns from IGN key ON
to point A show operation is started by diagnosis connec-
tor.
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20. Hydraulic Unit for ABS/TCS System

B4M0628
G: INSTALLATION
1) Install hydraulic unit and bracket.
Tightening torque:
32±7 N⋅m (3.3±0.7 kg-m, 23.9±5.1 ft-lb)
2) Connect brake pipes to their correct hydraulic unit con-
nections.
3) Connect connector to hydraulic unit.
4) Install canister.
5) Install air cleaner case.
6) Install air intake duct.
7) Connect ground cable to battery.
CAUTION:
Cover relay securely with rubber boot.
21. ABS/TCS Control Module
A: REMOVAL
1) Disconnect ground cable from battery.
2) Remove floor mat located under lower right side of front
seat.
B4M0643A
3) Remove screw which secure ABS/TCS control module
from the body.
4) Disconnect connector from ABS/TCS control module.
B: INSPECTION
Check that connector is connected correctly and that con-
nector terminal sliding resistance is correct.
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20. Hydraulic Unit for ABS/TCS System - 21. ABS/TCS Control Module

B4M0628
G: INSTALLATION
1) Install hydraulic unit and bracket.
Tightening torque:
32±7 N⋅m (3.3±0.7 kg-m, 23.9±5.1 ft-lb)
2) Connect brake pipes to their correct hydraulic unit con-
nections.
3) Connect connector to hydraulic unit.
4) Install canister.
5) Install air cleaner case.
6) Install air intake duct.
7) Connect ground cable to battery.
CAUTION:
Cover relay securely with rubber boot.
21. ABS/TCS Control Module
A: REMOVAL
1) Disconnect ground cable from battery.
2) Remove floor mat located under lower right side of front
seat.
B4M0643A
3) Remove screw which secure ABS/TCS control module
from the body.
4) Disconnect connector from ABS/TCS control module.
B: INSPECTION
Check that connector is connected correctly and that con-
nector terminal sliding resistance is correct.
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4-4SERVICE PROCEDURE
20. Hydraulic Unit for ABS/TCS System - 21. ABS/TCS Control Module

C: INSTALLATION
1) Connect connector to ABS/TCS control module.
2) Install ABS/TCS control module on the body.
CAUTION:

When installing seat rail, be careful no to have the
harness caught in the rail.

Cover the connector completely with rubber boot.
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21. ABS/TCS Control Module

22. Hydraulic Unit for ABS System
(ABS 5.3 Type)
B4M0994A
1Hydraulic control unit

2Damper

3Stud bolt

4Rear-RH outlet

5Rear-LH outlet

6Secondary inlet

7Primary inlet

8Front-LH outlet
9Front-RH outlet

10Cable clip

11Bracket

12Relay box

13Motor relay

14Valve relay

15Cap

16Connector bracket
Tightening torque: N⋅m (kg-m, ft-lb)
T1: 18±5 (1.8±0.5, 13.0±3.6)
T2: 29±7 (3.0±0.7, 21.7±5.1)
T3: 32±10 (3.3±1.0, 24±7)
A: REMOVAL
1. HYDRAULIC UNIT
1) Disconnect ground cable from battery.
2) Remove air intake duct and canister from engine com-
partment to facilitate removal of hydraulic unit.
3) Disconnect connector from hydraulic unit.
4) Unlock cable clip.
5) Disconnect brake pipes from hydraulic unit.
CAUTION:
Wrap brake pipes with vinyl bag to avoid spilling brake
fluid on vehicle body.
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22. Hydraulic Unit for ABS System (ABS 5.3 Type)

B4M0996
6) Remove nuts and bolt which secure hydraulic unit
bracket, and remove hydraulic unit from engine compart-
ment.
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.

When a new hydraulic unit is installed, apply a coat
of rust-preventive wax (Nippeco LT or GB) to bracket
attaching bolt after tightening.

Do not pull harness disconnecting harness connec-
tor.
2. RELAY BOX
1) Disconnect ground cable from battery.
2) Remove air intake duct and canister from engine com-
partment to facilitate removal of relay box.
B4M1029
3) Disconnect connector from relay box.
4) Unlock cable clip.
5) Remove nuts which secure relay box, and remove relay
box and connector bracket.
CAUTION:
Do not drop or bump relay box.
11 0
4-4SERVICE PROCEDURE
22. Hydraulic Unit for ABS System (ABS 5.3 Type)