Subaru Legacy IV (2008 year). Manual - part 922

VDC(diag)-3

Basic Diagnostic Procedure

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

4

PERFORM DIAGNOSIS.
1) Refer to “List of Diagnostic Trouble Code 
(DTC)”.

NOTE:
For the DTC list, refer to “List of Diagnostic
Trouble Code (DTC)”. <Ref. to VDC(diag)-34,
LIST, List of Diagnostic Trouble Code (DTC).>
2) Correct the cause of trouble.
3) Perform the Clear Memory Mode. <Ref. to 
VDC(diag)-23, OPERATION, Clear Memory 
Mode.>
4) Perform the Inspection Mode. <Ref. to 
VDC(diag)-22, PROCEDURE, Inspection 
Mode.>
5) Read the DTC. <Ref. to VDC(diag)-21, 
OPERATION, Read Diagnostic Trouble Code 
(DTC).>

Is DTC displayed?

Repeat step 4 until 
DTC is not shown.

Finish the diagno-
sis.

Step

Check

Yes

No

VDC(diag)-4

Check List for Interview

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

2. Check List for Interview

A: CHECK

Check the following item about the vehicle’s state.

1. STATE OF ABS WARNING LIGHT

ABS warning light 
illuminates.

 Always
 Sometimes
 Only once
 Does not come on

• When/How long does it illuminate?

Ignition key position

 LOCK
 ACC
 ON (before starting engine)
 START
 ON (after starting engine, engine is running)
 ON (after starting engine, engine is at a standstill)

Timing

 Immediately after turning the ignition switch to ON
 Immediately after turning the ignition switch to START

 While accelerating

 —

km/h

 

—

MPH

 While driving at a constant speed

km/h

MPH

 While 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 other electrical parts are operating

• Part name:
• Operating condition:

VDC(diag)-5

Check List for Interview

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

2. STATE OF VDC WARNING LIGHT AND VDC OFF INDICATOR LIGHT

3. STATE OF VDC INDICATOR LIGHT

VDC warning light 
and VDC OFF indi-
cator light illuminate.

 Always
 Sometimes
 Only once
 Does not come on

• When/How long does it illuminate?

Ignition key position

 LOCK
 ACC
 ON (before starting engine)
 START
 ON (after starting engine, engine is running)
 ON (after starting engine, engine is at a standstill)

Timing

 Immediately after turning the ignition switch to ON
 Immediately after turning the ignition switch to START

 While accelerating

 —

km/h

 

—

MPH

 While driving at a constant speed

km/h

MPH

 While 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 other electrical parts are operating

• Part name:
• Operating condition:

VDC operation indi-
cator light illuminate.

 Always
 Sometimes
 Only once
 Does not come on

• When/How long does it illuminate?

Ignition key position

 LOCK
 ACC
 ON (before starting engine)
 START
 ON (after starting engine, engine is running)
 ON (after starting engine, engine is at a standstill)

Timing

 Immediately after turning the ignition switch to ON
 Immediately after turning the ignition switch to START

 While accelerating

 —

km/h

 

—

MPH

 While driving at a constant speed

km/h

MPH

 While 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 other electrical parts are operating

• Part name:
• Operating condition:

VDC(diag)-6

Check List for Interview

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

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
 Straight road
 Sharp curve
 Gentle curve
 S-curve
 Road with a slope on both sides
 Others:

d) Road surface

 Dry
 Wet
 Covered with fresh snow
 Covered with hardened snow
 Frozen slope
 Others: