Subaru Outback: Basic Diagnostic Procedure
A: PROCEDURE
CAUTION:
Remove foreign matter (dust, water, oil etc.) from the VDCCM&H/U connector
during removal and installation.
NOTE:
- To check the harness for open or short circuits, shake problem spot or
connector.
- Refer to "Check List for Interview". <Ref. to VDC(diag)-4, Check List
for Interview.>


Check List for Interview
A: CHECK
Check the following item about the vehicle's state.
1. STATE OF ABS WARNING LIGHT

2. STATE OF VDC WARNING LIGHT & VDC INDICATOR LIGHT

3. STATE OF VDC OFF INDICATOR LIGHT

4. CONDITIONS UNDER WHICH TROUBLE OCCURS


General Description
A: CAUTION
1. SUPPLEMENTAL RESTRAINT SYSTEM
"AIRBAG"
Airbag system wiring harness is routed near the
ABS wheel speed sensor and VDCCM&H/U.
CAUTION:
- Do not use electrical test devices on airbag
system wiring harnesses or connector circuits.
- Be careful not to damage the airbag system
wiring harness when servicing the ABS wheel
speed sensor and VDCCM&H/U.
B: INSPECTION
Before performing diagnosis, check the following
items which might affect VDC 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 (GV) bolt for
VDC.
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 VDC-12, CHECKING
THE HYDRAULIC UNIT ABS OPERATION WITH
THE BRAKE TESTER, INSPECTION, VDC Control
Module and Hydraulic Control Unit (VDCCM&
H/U).>
- Without brake tester <Ref. to VDC-12, CHECKING
THE HYDRAULIC UNIT ABS OPERATION
BY PRESSURE GAUGE, INSPECTION, VDC
Control Module and Hydraulic Control Unit (VDCCM&
H/U).>
5. BRAKE DRAG
Check for brake drag.
6. BRAKE PAD AND ROTOR
Check the brake pad and rotor.
- Front <Ref. to BR-17, INSPECTION, Front Brake
Pad.> <Ref. to BR-19, INSPECTION, Front Disc
Rotor.>
- Rear <Ref. to BR-31, INSPECTION, Rear Brake
Pad.> <Ref. to BR-34, INSPECTION, Rear Disc
Rotor.>
7. TIRE
Check the tire specifications, tire wear and air pressure.
<Ref. to WT-2, SPECIFICATION, General
Description.>
C: PREPARATION TOOL
1. SPECIAL TOOL

2. GENERAL TOOL

Electrical Component Location
A: LOCATION

- VDC control module & hydraulic
control unit (VDCCM&H/U)
- Connector
- VDC OFF switch
- ABS warning light
- Brake warning light (EBD warning
light)
- VDC warning light & VDC indicator
light
- VDC OFF indicator light
- Steering angle sensor
- Transmission control module
(TCM)
- Data link connector
- Magnetic encoder
- ABS wheel speed sensor
- Engine control module (ECM)
- Stop light & brake switch

Control Module I/O Signal
A: ELECTRICAL SPECIFICATION

NOTE:
- Terminal numbers in VDCCM&H/U connector are shown in the figure.
- When the connector is removed from VDCCM&H/U, the brake warning light (EBD
warning light), ABS
warning light, and VDC warning light & VDC indicator light illuminate.

B: WIRING DIAGRAM

- Battery
- Ignition switch
- VDC control module & hydraulic
control unit (VDCCM&H/U)
- VDC control module
- Valve relay
- Pressure sensor
- Yaw rate & G sensor
- Motor relay
- Motor
- Front inlet solenoid valve LH
- Front outlet solenoid valve LH
- Front inlet solenoid valve RH
- Front outlet solenoid valve RH
- Rear inlet solenoid valve LH
- Rear outlet solenoid valve LH
- Rear inlet solenoid valve RH
- Rear outlet solenoid valve RH
- Primary cut solenoid valve
- Primary suction solenoid valve
- Secondary cut solenoid valve
- Secondary suction solenoid valve
- Data link connector
- VDC OFF switch
- Combination meter
- VDC OFF indicator light
- VDC warning light & VDC indicator
light
- ABS warning light
- Brake warning light (EBD warning
light)
- Brake fluid level switch
- Stop light switch
- Stop light
- Body integrated unit
- Engine control module (ECM)
- Transmission control module
(TCM)
- Parking brake control module
- Steering angle sensor
- Clutch stroke sensor (MT model
only)
- Front ABS wheel speed sensor LH
- Front ABS wheel speed sensor
RH
- Rear ABS wheel speed sensor LH
- Rear ABS wheel speed sensor
RH
READ NEXT:
A: OPERATION
1. HOW TO USE SUBARU SELECT MONITOR
NOTE:
For detailed operation procedures, refer to "PC
application help for Subaru Select Monitor".
If VDC and Subaru Select Monitor cannot communic
A: INSPECTION
Ignition switch
OFF
ON
Engine start
ABS warning light
Light OFF
Light ON
2 sec.
VDC OFF indicator light
VDC warning light & VDC indicator
light
Several seconds (dependi
A: LIST
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
A: DTC C0021 FRONT RIGHT ABS SENSOR CIRCUIT OPEN OR SHORT
NOTE:
For the diagnostic procedure, refer to "DTC C0027 REAR LEFT ABS SENS
SEE MORE:
WARNING
● When the electronic parking brake cannot be released, the electronic parking
brake system may malfunction. Driving in such conditions may cause an unexpected
accident. Contact your SUBARU dealer for inspection as soon as possible.
● You can release the electronic parking
A: INSPECTION
1) Perform a diagnosis code (DTC) check by connecting the Subaru Select
Monitor.
2) If any diagnosis code (DTC) is displayed, refer to "List of Diagnostic
Trouble Code (DTC)" in "HVAC SYSTEM
(DIAGNOSTICS)" section. <Ref. to AC(diag)-53, LIST, List of Diagnostic Trouble
Code (DTC
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