Subaru Legacy (2005 year). Manual - part 760

ABS(diag)-5

ABS (DIAGNOSTICS)

Check List for Interview

2. STATE OF BRAKE WARNING LIGHT

Brake warning light 
comes on.

❏ Always

❏ Sometimes

❏ Only once

❏ Not come on

❏ When pulling the parking brake lever up.

❏ When releasing the parking brake lever down.

• When / how long does it come on?

Ignition key position

❏ LOCK

❏ ACC

❏ ON (before starting engine)

❏ START

❏ ON (after Engine starting, engine is running)

❏ ON (after Engine starting, engine is at a standstill)

Timing

❏ Immediately after turning the ignition to ON

❏ Immediately after turning the ignition to START
❏ When accelerating

—

km/h

—

MPH

❏ When driving at a constant speed

km/h

MPH

❏ When decelerating

—

km/h

—

MPH

❏ When turning to the right

Steering angle:

deg

Steering time:

Sec.

❏ When turning to the left

Steering angle:

deg

Steering time:

Sec.

❏ When operating other electrical parts
• Parts name:

• Operating condition:

ABS(diag)-6

ABS (DIAGNOSTICS)

Check List for Interview

3. SYMPTOMS

ABS operating condi-
tion

❏ Does not move.
❏ Operates only when applying an abrupt brake.

Vehicle speed:

km/h

MPH

• How to step on brake pedal:
a) Operating time:

Sec.

b) Operating noise: 

❏ Occurs. / ❏ Does not occur.

• What kind of noise?

❏ Knocking

❏ Gong gong

❏ Bong

❏ Buzz

❏ Gong gong buzz

❏ Others:

c) Reaction force of brake pedal

❏ Stick

❏ Weak pedal resistance

❏ Strong pedal resistance

❏ Others:

Behavior of vehicle

a) Directional stability cannot be obtained or the steering refuses to work when applying brakes:
❏ Yes / ❏ No
• When:

❏ When turning to the right

❏ When turning to the left

❏ When spinning

❏ Others:

b) Directional stability cannot be obtained or the steering refuses to work when accelerating:
❏ Yes / ❏ No
• When:

❏ When turning to the right

❏ When turning to the left

❏ When spinning

❏ Others:

c) Poor brake performance: 

❏ Yes / ❏ No

• What kind:

❏ Long braking/stopping distance

❏ Brakes lock or drag

❏ Long pedal stroke

❏ Pedal sticks.

❏ Others:

d) Poor acceleration: 

❏ Yes / ❏ No

• What kind:

❏ Not accelerate

❏ Engine stalls.

❏ Others:

e) Occurrence of vibration: 

❏ Yes / ❏ No

• Where

• What kind:
f) Occurrence of noise: 

❏ Yes / ❏ No

• Where

• What kind:
g) Other troubles occurred: 

❏ Yes / ❏ No

• What kind:

ABS(diag)-7

ABS (DIAGNOSTICS)

Check List for Interview

4. CONDITIONS UNDER WHICH TROUBLE OCCURS

Environment

a) Weather

❏ Fine

❏ Cloudy

❏ Rainy

❏ Snowy

❏ Others:

b) Ambient temperature

°C (°F)

c) Road

❏ Inner city

❏ Suburbs

❏ Highway

❏ Local street

❏ Uphill

❏ Downhill

❏ Paved road

❏ Gravel road

❏ Muddy road

❏ Sandy place

❏ Others:

d) Road surface

❏ Dried

❏ Wet

❏ Covered with fresh snow

❏ Covered with hardened snow

❏ Frozen slope

❏ Others:

Condition

a) Brakes

Deceleration:

G

❏ Intermittent / ❏ Temporary

b) Accelerator

Acceleration:

G

❏ Intermittent / ❏ Temporary

c) Vehicle speed

km/h

MPH

❏ Advancing

❏ When accelerating

❏ When decelerating

❏ At low speed

❏ When turning

❏ Others:

d) Tire inflation pressure

Front RH tire:

kPa

Front LH tire:

kPa

Rear RH tire:

kPa

Rear LH tire:

kPa

e) Degree of wear

Front RH tire:

Front LH tire:

Rear RH tire:

Rear LH tire:

f) Genuine parts are used.: 

❏ Yes / ❏ No

g) Tire chain is attached.: 

❏ Yes / ❏ No

h) T-type tire is used.: 

❏ Yes / ❏ No

i) Condition of suspension alignment:

j) Loading state:

k) Repair parts are used.: 

❏ Yes / ❏ No

• Contents:
l) Others:

ABS(diag)-8

ABS (DIAGNOSTICS)

General Description

3. General Description

A: CAUTION

1. SUPPLEMENTAL RESTRAINT SYSTEM 
“AIRBAG”

Airbag system wiring harness is routed near the
ABS wheel speed sensor and ABSCM&H/U.

CAUTION:
• All airbag system wiring harness and con-
nectors are colored yellow. Do not use the elec-
trical test equipment on these circuits.
• Be careful not to damage the airbag system
wiring harness when servicing the ABS wheel
speed sensor and ABSCM&H/U.

B: INSPECTION

Before performing diagnosis, check the following
items which might affect ABS problems.

1. BATTERY

Measure battery voltage and check electrolyte.

Standard voltage: 12 V or more

Specific gravity: More than 1.260

2. GROUND

Check the tightening torque of ABS ground (GB-7)
bolt.

Tightening torque:

13 N

⋅

m (1.3 kgf-m, 9.6 ft-lb)

3. BRAKE FLUID

1) Check the brake fluid level.
2) Check the brake fluid for leaks.

4. HYDRAULIC UNIT

Check the hydraulic unit.
• With brake tester <Ref. to ABS-8, CHECKING
THE HYDRAULIC UNIT ABS OPERATION WITH
BRAKE TESTER, INSPECTION, ABS Control
Module and Hydraulic Control Unit (ABSCM&H/
U).>
• Without brake tester <Ref. to ABS-7, CHECK-
ING THE HYDRAULIC UNIT ABS OPERATION
BY PRESSURE GAUGE, INSPECTION, ABS
Control Module and Hydraulic Control Unit (AB-
SCM&H/U).>

5. BRAKE DRAG

Check for brake drag.

6. BRAKE PAD AND ROTOR

Check the brake pad and rotor.
• FRONT <Ref. to BR-18, INSPECTION, Front
Brake Pad.>    <Ref. to BR-19, INSPECTION, Front
Disc Rotor.>
• REAR <Ref. to BR-25, INSPECTION, Rear
Brake Pad.> <Ref. to BR-26, INSPECTION, Rear
Disc Rotor.>

7. TIRE

Check the tire specifications, tire wear and air pres-
sure. <Ref. to WT-2, SPECIFICATION, General
Description.>