Subaru Legacy (2005 year). Manual - part 805

VDC(diag)-85

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AN:DTC C0052 MOTOR

DTC DETECTING CONDITION:
• Defective motor
• Defective motor relay
• Defective harness connector
TROUBLE SYMPTOM:
• ABS does not operate.
• VDC does not operate.
• EBD may not operate.

NOTE:
For the diagnostic procedure, refer to DTC C0052 “MOTOR / MOTOR RELAY MALFUNCTION” <Ref. to
VDC(diag)-81, DTC C0052 MOTOR/MOTOR RELAY MALFUNCTION, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>

Step

Check

Yes

No

1

CHECK MOTOR RELAY FOR VDCCM&H/U.
1) Disconnect the connector from VDCCM&H/
U.
2) Measure the resistance between 
VDCCM&H/U connector terminals.

Terminals

No. 9 — No. 10:

Is the resistance more than 1 
M

Ω?

Go to step 2.

Replace the 
VDCCM&H/U. 
<Ref. to VDC-7, 
VDC Control Mod-
ule and Hydraulic 
Control Unit 
(VDCCM&H/U).>

2

CHECK VDCCM&H/U.
1) Connect all the connectors.
2) Perform the clear memory mode.
3) Perform the inspection mode.
4) Read the DTC.

Is the same DTC displayed?

Replace the 
VDCCM&H/U. 
<Ref. to VDC-7, 
VDC Control Mod-
ule and Hydraulic 
Control Unit 
(VDCCM&H/U).>

Go to step 3.

3

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to 
DTC. <Ref. to 
VDC(diag)-38, List 
of Diagnostic Trou-
ble Code (DTC).>

Temporary poor 
contact occurs.

NOTE:
Though the ABS
warning light re-
mains on at this
time, it is normal.
Drive the vehicle at
more than 12 km/h
(7 MPH) in order to
turn ABS warning
light off. Be sure to
drive the vehicle
and check the
warning light goes
off.

VDC(diag)-86

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AO:DTC C0054 BLS OPEN CIRCUIT

DTC DETECTING CONDITION:
Defective stop light switch
TROUBLE SYMPTOM:
• ABS does not operate.
• VDC does not operate.
WIRING DIAGRAM:

VDC00322

MAIN SBF

SBF-2

No.8

B310

B159

E

37

VDCCM & H/U

B64

:   OC

B65

B65

B310

B159

1 2
3 4

B64

1 2

59

2

3

2

1

OC WC

9

4

7

6

2

1
5

3
8

1 2 3 4

11 12 13 14
27 28 29 30

15 16 17 18
31 32 33 34

19 20 21 22
35 36 37 38

23 24 25 26
39 40 41 42

5

6

7

8

9

10

:   WC

WC   :

OC   :

BATTERY

STOP LIGHT SWITCH

WITH CRUISE CONTROL

WITHOUT CRUISE CONTROL

VDC(diag)-87

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Step

Check

Yes

No

1

CHECK OUTPUT OF STOP LIGHT SWITCH 
WITH SUBARU SELECT MONITOR.
1) Select {Current Data Display & Save} in 
Subaru Select Monitor.
2) Release the brake pedal.
3) Read the stop light switch output in Subaru 
Select Monitor.

Is OFF displayed on the dis-
play screen?

Go to step 2.

Go to step 3.

2

CHECK OUTPUT OF STOP LIGHT SWITCH 
WITH SUBARU SELECT MONITOR.
1) Depress the brake pedal.
2) Read the stop light switch output in Subaru 
Select Monitor.

Is ON displayed on the display 
screen?

Go to step 5.

Go to step 3.

3

CHECK IF STOP LIGHTS COME ON.
Depress the brake pedal.

Does the stop light illuminate? Go to step 4.

Repair the stop 
lights circuit.

4

CHECK OPEN CIRCUIT OF HARNESS.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from VDCCM&H/
U.
3) Depress the brake pedal.
4) Measure the voltage between VDCCM&H/
U connector and chassis ground.

Connector & terminal

(B310) No. 37 (+) — Chassis ground (

−

):

Is the voltage 10 — 15 V?

Go to step 5.

Repair the har-
ness between stop 
light switch and 
VDCCM&H/U con-
nector.

5

CHECK POOR CONTACT IN CONNECTORS. Is there poor contact in con-

nector between stop light 
switch and VDCCM&H/U?

Repair the con-
nector.

Go to step 6.

6

CHECK VDCCM&H/U.
1) Connect all the connectors.
2) Perform the clear memory mode.
3) Perform the inspection mode.
4) Read the DTC.

Is the same DTC displayed?

Replace the 
VDCCM&H/U. 
<Ref. to VDC-7, 
VDC Control Mod-
ule and Hydraulic 
Control Unit 
(VDCCM&H/U).>

Go to step 7.

7

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to 
DTC.

Temporary poor 
contact occurs.

VDC(diag)-88

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AP:DTC C0054 BLS ON MALFUNCTION

DTC DETECTING CONDITION:
Defective stop light switch
TROUBLE SYMPTOM:
• ABS does not operate.
• VDC does not operate.
WIRING DIAGRAM:

VDC00322

MAIN SBF

SBF-2

No.8

B310

B159

E

37

VDCCM & H/U

B64

:   OC

B65

B65

B310

B159

1 2
3 4

B64

1 2

59

2

3

2

1

OC WC

9

4

7

6

2

1
5

3
8

1 2 3 4

11 12 13 14
27 28 29 30

15 16 17 18
31 32 33 34

19 20 21 22
35 36 37 38

23 24 25 26
39 40 41 42

5

6

7

8

9

10

:   WC

WC   :

OC   :

BATTERY

STOP LIGHT SWITCH

WITH CRUISE CONTROL

WITHOUT CRUISE CONTROL