General Description - Subaru LEGACY 2003 Service Manual

ABS (DIAGNOSTICS)

3. General Description

A: CAUTION
1. SUPPLEMENTAL RESTRAINT SYSTEM
"AIRBAG"
Airbag system wiring harness is routed near the
ABS sensor, ABS control module and hydraulic
control unit.
CAUTION:
• All airbag system wiring harness and con-
nectors are colored yellow. Do not use electri-
cal test equipment on these circuit.
• Be careful not to damage airbag system wir-
ing harness when servicing the ABS sensor,
ABS control module and hydraulic control unit.
B: INSPECTION
Before performing diagnostics, check the following
items which might affect ABS problems:
1. BATTERY
Measure battery voltage and specific gravity of
electrolyte.
Standard voltage: 12 V, or more
Specific gravity: Above 1.260
2. BRAKE FLUID
1) Check brake fluid level.
2) Check brake fluid leakage.
3. 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).>
4. BRAKE DRAG
Check brake drag.
5. BRAKE PAD AND ROTOR
Check brake pad and rotor.
• Front <Ref. to BR-21, INSPECTION, Front
Brake Pad.> and <Ref. to BR-22, INSPECTION,
Front Disc Rotor.>
• Rear <Ref. to BR-26, INSPECTION, Rear Brake
Pad.> and <Ref. to BR-27, INSPECTION, Rear
Disc Rotor.>
GENERAL DESCRIPTION
6. TIRE
Check tire specifications, tire wear and air pres-
sure. <Ref. to WT-2, SPECIFICATIONS, General
Description.>
ABS-8