Subaru 2009 IMPREZA Service Manual page 2387

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:
• Do not use electrical test equipment on wir-
ing harness and connector circuits of the air-
bag system.
• 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
item which might affect ABS problems.
1. BATTERY
Measure the battery voltage and check electrolyte.
Standard voltage:
12 V or more
Specific gravity:
1.260 or more
2. GROUND
Check the tightening torque of ground (GB-5) bolt
of ABS.
Tightening torque:
13 N·m (1.3 kgf-m, 9.6 ft-lb)
C: PREPARATION TOOL
1. SPECIAL TOOL
ILLUSTRATION
ST1B022XU0
2. GENERAL TOOL
TOOL NAME
Circuit tester
Oscilloscope
General Description
TOOL NUMBER DESCRIPTION
1B022XU0 SUBARU SELECT
MONITOR III KIT
ABS(diag)-7
3. BRAKE FLUID
1) Check the brake fluid level.
2) Check the brake fluid for leaks.
4. HYDRAULIC UNIT
Check the hydraulic unit.
• When using the brake tester <Ref. to ABS-8,
CHECKING THE HYDRAULIC UNIT ABS OPERA-
TION WITH THE BRAKE TESTER, INSPECTION,
ABS Control Module and Hydraulic Control Unit
(ABSCM&H/U).>
• When not using the brake tester <Ref. to ABS-7,
CHECKING THE HYDRAULIC UNIT ABS OPERA-
TION BY PRESSURE GAUGE, INSPECTION,
ABS Control Module and Hydraulic Control Unit
(ABSCM&H/U).>
5. BRAKE DRAG
Check for brake drag.
6. BRAKE PAD AND ROTOR
Check the brake pad and rotor.
• Front <Ref. to BR-14, INSPECTION, Front Brake
Pad.> <Ref. to BR-15, INSPECTION, Front Disc
Rotor.>
• Rear <Ref. to BR-20, INSPECTION, Rear Brake
Pad.> <Ref. to BR-21, INSPECTION, Rear Disc
Rotor.>
7. TIRE
Check the tire specifications, tire wear and air pres-
sure. <Ref. to WT-2, SPECIFICATION, General
Description.>
Used for troubleshooting the electrical system.
REMARKS
Used for measuring resistance, voltage and current.
Used for measuring the sensor.
ABS (DIAGNOSTICS)
REMARKS