Subaru LEGACY 2003 Service Manual page 129

DIAGNOSTICS CHART WITH DIAGNOSIS CONNECTOR
Step
1 CHECK GROUND CIRCUIT OF PRESSURE
SENSOR.
1) Turn ignition switch to OFF.
2) Disconnect connector (F91) from VDCH/U.
3) Measure resistance between VDCH/U con-
nector and chassis ground.
Connector & terminal
(F91) No. 15 — Chassis ground:
Is the measured value less than the speci-
fied value?
2 CHECK GROUND CIRCUIT OF VDCCM.
1) Disconnect connector from VDCCM.
2) Remove cover from VDCCM. <Ref. to
VDC-19, REMOVE, VDCCM Connector
Cover.>
3) Connect connector to VDCCM.
4) Measure resistance between VDCCM and
chassis ground.
Connector & terminal
(F87) No. 76 — Chassis ground:
Is the measured value less than the speci-
fied value?
3 CHECK POOR CONTACT IN CONNECTORS.
Is there poor contact in VDCCM connector?
4 CHECK POWER SUPPLY OF PRESSURE
SENSOR.
NOTE:
When this inspection is carried out, DTC 51 AB-
NORMAL VALVE RELAY is memorized, but
this does not indicate valve relay malfunction.
1) Turn ignition switch to ON.
2) Measure voltage between VDCH/U con-
nector terminals.
Connector & terminal
(F91) No. 16 (+) — No. 15 ( − − − − ):
Is the measured value within the specified
range?
5 CHECK POWER SUPPLY OF VDCCM.
1) Turn ignition switch to OFF.
2) Disconnect connector from VDCCM.
3) Remove cover from VDCCM. <Ref. to
VDC-19, REMOVE, VDCCM Connector
Cover.>
4) Connect connector to VDCCM.
5) Turn ignition switch to ON.
6) Measure voltage between VDCCM connec-
tor terminals.
Connector & terminal
(F87) No. 78 (+) — No. 76 ( − − − − ):
Is the measured value within the specified
range?
6 CHECK POOR CONTACT IN CONNECTORS.
Is there poor contact in VDCCM connector?
Value
0.5 Ω
0.5 Ω
There is poor contact.
4.75 — 5.25 V
4.75 — 5.25 V
There is poor contact.
VDC-127
VDC (DIAGNOSTICS)
Yes
Go to step 4. Go to step 2.
Replace harness Go to step 3.
between VDCH/U
and VDCCM.
Repair or replace Replace VDCCM.
VDCCM connec- <Ref. to VDC-8,
tor. VDC Control Mod-
ule (VDCCM).>
Go to step 7. Go to step 5.
Repair harness Go to step 6.
between VDCH/U
and VDCCM.
Repair or replace Replace VDCCM.
VDCCM connec- <Ref. to VDC-8,
tor. VDC Control Mod-
ule (VDCCM).>
No