Subaru LEGACY 2003 Service Manual page 197

DIAGNOSTICS CHART WITH SELECT MONITOR
Step
1 CHECK GROUND SHORT OF HARNESS.
1) Turn ignition switch to OFF.
2) Disconnect connector from VDCCM and
ECM.
3) Measure resistance between VDCCM and
ECM.
Connector & terminal
(F87) No. 75 — Chassis ground:
Does the measured value exceed the spec-
ified value?
2 CHECK INPUT VOLTAGE FROM ECM.
1) Connect connector to VDCCM.
2) Turn ignition switch to ON.
3) Measure voltage between ECM and chas-
sis ground.
Connector & terminal
H4 engine RHD without OBD model
(B134) No. 25 (+) — Chassis ground ( − − − − ):
H4 engine RHD with OBD model
(B134) No. 33 (+) — Chassis ground ( − − − − ):
H4 engine LHD model
(B134) No. 25 (+) — Chassis ground ( − − − − ):
H6 engine model
(B136) No. 11 (+) — Chassis ground ( − − − − ):
Is the measured value within the specified
range?
3 CHECK POOR CONTACT IN ECM CONNEC-
TORS.
Is there poor contact in ECM connector?
4 ERASE MEMORY.
1) Connect all connectors.
2) Erase the memory.
Can the memory be erased?
5 CHECK DIAGNOSTIC TROUBLE CODE.
1) Perform inspection mode.
2) Read out the diagnostic trouble code.
Is the same diagnostic trouble code as in
the current diagnosis still being output?
Value
1 MΩ
10 — 15 V
There is poor contact.
Can be erased.
Same DTC indicated.
VDC-195
VDC (DIAGNOSTICS)
Yes
Go to step 2. Repair or replace
ground short cir-
cuit between
VDCCM and ECM.
Go to step 4. Go to step 3.
Replace ECM. Repair or replace
<Ref. to ECM connector.
FU(H6DO)-46,
Engine Control
Module.>
Go to step 5. Replace VDCCM.
<Ref. to VDC-8,
VDC Control Mod-
ule (VDCCM).>
Replace ECM. A temporary poor
<Ref. to contact.
FU(H6DO)-46,
Engine Control
Module.>
No