Subaru Legacy III (2000-2003 year). Manual - part 779

VDC-152

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

4

CHECK BATTERY SHORT OF SOLENOID 
VALVE.
1) Turn ignition switch to ON.
2) Measure voltage between VDCH/U con-

nector and chassis ground.

Connector & terminal

DTC 31/(VDC5) No. 5 (+) — Chassis 
ground (

−−−−

):

DTC 33/(VDC5) No. 8 (+) — Chassis 
ground (

−−−−

):

DTC 35/(VDC5) No. 7 (+) — Chassis 
ground (

−−−−

):

DTC 37/(VDC5) No. 6 (+) — Chassis 
ground (

−−−−

):

DTC 61/(VDC5) No. 9 (+) — Chassis 
ground (

−−−−

):

DTC 62/(VDC5) No. 12 (+) — Chassis 
ground (

−−−−

):

Is the measured value less than the speci-
fied value?

1 V

Go to step 5.

Replace VDCH/U.  
<Ref. to VDC-8, 
VDC Control Mod-
ule (VDCCM).>

5

CHECK BATTERY SHORT OF HARNESS.
1) Turn ignition switch to OFF.
2) Measure voltage between VDCCM connec-

tor and chassis ground.

Connector & terminal

DTC 31/(F87) No. 30 (+) — Chassis 
ground (

−−−−

):

DTC 33/(F87) No. 24 (+) — Chassis 
ground (

−−−−

):

DTC 35/(F87) No. 23 (+) — Chassis 
ground (

−−−−

):

DTC 37/(F87) No. 31 (+) — Chassis 
ground (

−−−−

):

DTC 61/(F87) No. 25 (+) — Chassis 
ground (

−−−−

):

DTC 62/(F87) No. 26 (+) — Chassis 
ground (

−−−−

):

Is the measured value less than the speci-
fied value?

1 V

Go to step 6.

Repair harness 
between VDCCM 
and VDCH/U.

6

CHECK BATTERY SHORT OF HARNESS.
1) Turn ignition switch to ON.
2) Measure voltage between VDCCM connec-

tor and chassis ground.

Connector & terminal

DTC 31/(F87) No. 30 (+) — Chassis 
ground (

−−−−

):

DTC 33/(F87) No. 24 (+) — Chassis 
ground (

−−−−

):

DTC 35/(F87) No. 23 (+) — Chassis 
ground (

−−−−

):

DTC 37/(F87) No. 31 (+) — Chassis 
ground (

−−−−

):

DTC 61/(F87) No. 25 (+) — Chassis 
ground (

−−−−

):

DTC 62/(F87) No. 26 (+) — Chassis 
ground (

−−−−

):

Is the measured value less than the speci-
fied value?

1 V

Go to step 7.

Repair harness 
between VDCCM 
and VDCH/U.

Step

Value

Yes

No

VDC-153

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

7

CHECK GROUND SHORT OF HARNESS.
1) Turn ignition switch to OFF.
2) Measure resistance between VDCCM con-

nector and chassis ground.

Connector & terminal

DTC 31/(F87) No. 30 — Chassis ground:
DTC 33/(F87) No. 24 — Chassis ground:
DTC 35/(F87) No. 23 — Chassis ground:
DTC 37/(F87) No. 31 — Chassis ground:
DTC 61/(F87) No. 25 — Chassis ground:
DTC 62/(F87) No. 26 — Chassis ground:

Does the measured value exceed the spec-
ified value?

1 M

Ω

Go to step 8.

Repair harness 
between VDCCM 
and VDCH/U.

8

CHECK HARNESS/CONNECTOR BETWEEN 
VDCCM AND VDCH/U.
1) Connect connector (F91) to VDCH/U.
2) Measure resistance between VDCCM con-

nector and VDCH/U connector.

Connector & terminal

DTC 31/(F87) No. 30 — (VDC2) No. 2:
DTC 33/(F87) No. 24 — (VDC2) No. 2:
DTC 35/(F87) No. 23 — (VDC2) No. 2:
DTC 37/(F87) No. 31 — (VDC2) No. 2:
DTC 61/(F87) No. 25 — (VDC2) No. 2:
DTC 62/(F87) No. 26 — (VDC2) No. 2:

Is the measured value within the specified 
range?

7 — 10 

Ω

Go to step 9.

Repair harness/
connector 
between VDCCM 
and VDCH/U.

9

CHECK POOR CONTACT IN CONNECTORS.
Is there poor contact in connectors between 
VDCCM and VDCH/U?

There is poor contact.

Repair connector.

Go to step 10.

10

CHECK VDCCM.
1) Connect all connectors.
2) Erase the memory.
3) Perform inspection mode.
4) Read out the diagnostic trouble code.

Is the same diagnostic trouble code as in 
the current diagnosis still being output?

Same DTC indicated.

Repair VDCCM.  
<Ref. to VDC-8, 
VDC Control Mod-
ule (VDCCM).>

Go to step 11.

11

CHECK ANY OTHER DIAGNOSTIC TROU-
BLE CODES APPEARANCE.
Are other diagnostic trouble codes being out-
put?

Other DTC indicated.

Proceed with the 
diagnosis corre-
sponding to the 
diagnostic trouble 
code.

A temporary poor 
contact.

Step

Value

Yes

No

VDC-154

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

Q: DTC 32 FR PRESSURE REDUCING VALVE MALFUNCTION (FRONT RIGHT 

OUTLET VALVE MALFUNCTION)

NOTE:
For diagnostic procedure, refer to DTC 64. <Ref. to VDC-156, DTC 64 NORMAL CLOSING VALVE 1 MAL-
FUNCTION (SECONDARY SUCTION VALVE MALFUNCTION), Diagnostics Chart with Select Monitor.>  

R: DTC 34 FL PRESSURE REDUCING VALVE MALFUNCTION (FRONT LEFT 

OUTLET VALVE MALFUNCTION)

NOTE:
For diagnostic procedure, refer to DTC 64. <Ref. to VDC-156, DTC 64 NORMAL CLOSING VALVE 1 MAL-
FUNCTION (SECONDARY SUCTION VALVE MALFUNCTION), Diagnostics Chart with Select Monitor.>  

S: DTC 36 RR PRESSURE REDUCING VALVE MALFUNCTION (REAR RIGHT 

OUTLET VALVE MALFUNCTION)

NOTE:
For diagnostic procedure, refer to DTC 64. <Ref. to VDC-156, DTC 64 NORMAL CLOSING VALVE 1 MAL-
FUNCTION (SECONDARY SUCTION VALVE MALFUNCTION), Diagnostics Chart with Select Monitor.>  

T: DTC 38 RL PRESSURE REDUCING VALVE MALFUNCTION (REAR LEFT 

OUTLET VALVE MALFUNCTION)

NOTE:
For diagnostic procedure, refer to DTC 64. <Ref. to VDC-156, DTC 64 NORMAL CLOSING VALVE 1 MAL-
FUNCTION (SECONDARY SUCTION VALVE MALFUNCTION), Diagnostics Chart with Select Monitor.>  

U: DTC 63 NORMAL CLOSING VALVE 2 MALFUNCTION (PRIMARY SUCTION 

VALVE MALFUNCTION)

NOTE:
For diagnostic procedure, refer to DTC 64. <Ref. to VDC-156, DTC 64 NORMAL CLOSING VALVE 1 MAL-
FUNCTION (SECONDARY SUCTION VALVE MALFUNCTION), Diagnostics Chart with Select Monitor.>  

VDC-155

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

MEMO: