Subaru Legacy IV (2008 year). Manual - part 898

ABS-8

ABS Control Module and Hydraulic Control Unit (ABSCM&H/U)

ABS

2. CHECKING THE HYDRAULIC UNIT ABS
OPERATION WITH THE BRAKE TESTER

1) Install the spare fuse to the FWD connector lo-
cated in the main fuse box for models without AT
VTD.

2) Since the MT model and AT VTD model cannot
cut off the AWD circuit, set the wheels other than
the measured one on free rollers.
3) Prepare for ABS sequence control.
<Ref. to ABS-10, ABS Sequence Control.>
4) Set the front wheels or rear wheels on the brake
tester and set the gear to “neutral”.

5) Operate the brake tester.
6) Perform ABS sequence control.
<Ref. to ABS-10, ABS Sequence Control.>

7) When the hydraulic unit begins to work, check
the following work sequence.

(1) The FL wheel performs decompression,
hold and compression in sequence, and subse-
quently the FR wheel repeats the cycle.
(2) The RR wheel performs decompression,
hold and compression in sequence, and subse-
quently the RL wheel repeats the cycle.

8) Read values indicated on the brake tester and
check if the fluctuation of the values between de-
compression and compression meets specifica-
tion.

9) After the inspection, depress the brake pedal
and check that it is not abnormally hard, and tight-
ness is normal.

D: REPLACEMENT

CAUTION:
• Because the seal of the ABSCM cannot be re-
placed, do not pull or peel it by lifting it up.
• Because the screw of the H/U will become
slightly worn in every replacement procedure, 5
times is the maximum number of times for re-
placement. If a problem is found such as not
being able to torque the screw to specifications
even before 5 replacement operations are per-
formed, replace the H/U body.
• When installing the ABSCM, always use new
screws.
• When the sealing surface of the ABSCM or H/
U is dirty or damaged and it cannot be removed
or repaired, replace with a new part.
1) Remove the ABSCM&H/U bracket. <Ref. to
ABS-6, REMOVAL, ABS Control Module and Hy-
draulic Control Unit (ABSCM&H/U).>
2) To prevent entry of foreign objects and brake flu-
id leakage, plug the oil pressure port of the AB-
SCM&H/U using a screw plug, etc.

(1) Main fuse box

(2) FWD connector

(1) Brake tester

ABS00392

(1)

(2)

ABS00136

(1)

ABS00137

(1)

Front

wheel

Rear

wheel

Initial value

1,000 N

(102 kgf, 225 lb)

1,000 N

(102 kgf, 225 lb)

When depressurized

500 N

(51 kgf, 112 lb)

or less

500 N

(51 kgf, 112 lb)

or less

When pressurized

1,000 N

(102 kgf, 225 lb)

or more

1,000 N

(102 kgf, 225 lb)

or more

ABS-9

ABS Control Module and Hydraulic Control Unit (ABSCM&H/U)

ABS

3) Set the pump motor section of the removed AB-
SCM&H/U face down on a vise.

NOTE:
Before securing a part in a vise, place cushioning
material such as wood blocks, aluminum plate or
cloth between the part and the vise.

4) Using TORX

bit E5, remove the four screws of

ABSCM.

NOTE:
These screws cannot be reused.

5) Slowly pull out the ABSCM upward from the H/U.

NOTE:
To prevent damaging of coil section, remove the
ABSCM straight up from H/U without twisting.
6) Make sure there is no dirt or damage on the seal-
ing surface of the H/U.

CAUTION:
• Do not clean the ABSCM and H/U by applying
compressed air.
• Even if damage is found on the H/U seal, do
not attempt repair by filing or with a metal
scraper. To remove the seal residue, always
use a plastic scraper. Do not use chemical such
as paint thinner, etc., to clean.
7) Position the coil of the new ABSCM to align with
the H/U valve.
8) To prevent deformation of the ABSCM housing
cover, hold the corner of ABSCM and install it to the
H/U without tilting.

9) Using a TORX

bit E5, attach/tighten new

screws in the order of (1) through (4).

CAUTION:
Always use new screws.

Tightening torque:

1.5 N·m (0.15 kgf-m, 1.1 ft-lb)

10) Check that there is no foreign matter in mating
surface between the ABSCM and H/U.
11) Using a TORX

bit E5, tighten the screws in the

order of (1) through (4) again.

Tightening torque:

3 N·m (0.3 kgf-m, 2.2 ft-lb)

12) Check that there is no gap in the mating sur-
face between ABSCM and H/U.
13) Install the ABSCM&H/U to the vehicle.

(1) Aluminum plate, etc.

(2) Vise

ABS00430

(1)

(2)

ABS00431

ABS00432

(4)

(2)

(1)

(3)

ABS-10

ABS Sequence Control

ABS

3. ABS Sequence Control

A: OPERATION

1) While the ABS sequence control is being per-
formed, the operation of the hydraulic unit can be
checked using the brake tester or pressure gauge
after the hydraulic unit solenoid valve operation.
2) ABS sequence control can be started by the
Subaru Select Monitor.

1. ABS SEQUENCE CONTROL WITH
SUBARU SELECT MONITOR

NOTE:
In the event of any trouble, the ABS sequence con-
trol will not operate.
1) Connect the Subaru Select Monitor to data link
connector under the driver’s side instrument panel
lower cover.
2) Turn the ignition switch to ON.
3) Run the “PC application for Subaru Select Mon-
itor”.
4) Set the Subaru Select Monitor to “Brake Control”
mode.
5) When the “Function Check Sequence” is select-
ed, the “ABS sequence control” will start.
6) Execute the following operations when the mes-
sage “Press the brake pedal so that the brake ped-
al force is between 100 and 150 kgf” is displayed.

(1) When using a brake tester, press the brake
pedal pad with a force of 1,000 N (102 kgf, 225
lb).
(2) When using a pressure gauge, press the
brake pedal so that the pressure gauge indi-
cates 3,500 kPa (36 kg/cm

, 511 psi).

7) Press the [OK] key after “Press OK” is displayed.
8) The brake system being operated is displayed
on the Subaru Select Monitor.

ABS-11

ABS Sequence Control

ABS

2. CONDITIONS FOR ABS SEQUENCE CONTROL

ABS00943

(1)

(2)

(3)

(4)

(5)

(6)

(7)

(8)

(9)

(10)

(11)

(12)

(13)

(14)

(24)

(25)

(28)

(27)

(26)

V max < 4 km/h (2.5 MPH)

OFF

(16)

(17)

OFF

(21)

(18)

OFF

(15)

(19)

(18)

(19)

V max < 10 km/h (6 MPH)

(16)

(17)

(16)

(21)

(18)

(22)

(23)

(20)

Content .. 896 897 898 899 ..