Subaru Legacy 2004 Service Manual page 3099

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
• With the vehicle jack-up/lift-up or set on free rollers, when the wheels lock or spin after starting the engine,
ABS warning light, VDC warning light and VDC OFF indicator light may illuminate because VDCCM&H/U de-
tects the abnormal conditions from ABS wheel speed sensors. In this case, this is not a malfunction. Perform
the clear memory mode.
B: VDC WARNING LIGHT, VDC OFF INDICATOR LIGHT AND VDC INDICATOR
LIGHT DO NOT COME ON
DETECTING CONDITION:
• Defective combination meter
• Defective CAN communication
TROUBLE SYMPTOM:
When the ignition switch is turned to ON (engine OFF), VDC indicator light, VDC warning light and VDC OFF
indicator light do not come on.
NOTE:
When pressing VDC OFF switch for more than 10 seconds, VDC OFF indicator light goes off and cannot op-
erate any more. When turning the ignition switch from OFF to ON, the OFF operation enabled status is re-
stored.
Step
1 CHECK OTHER INDICATOR LIGHT.
Turn the ignition switch to ON.
2 CHECK VDCCM.
When the engine does not start, display the
current data of VDCCM using Subaru Select
Monitor.
3 CHECK LAN SYSTEM.
Perform the diagnosis for LAN system. <Ref. to
LAN(diag)-24, OPERATION, Read Diagnostic
Trouble Code (DTC).>
4 CHECK COMBINATION METER.
Check the combination meter.
Warning Light Illumination Pattern
Does other indicator light illu-
minate soon after "ON"?
Is "VDC warning light" output
set to "ON"?
Is there any fault in LAN sys-
tem?
Is combination meter OK?
VDC(diag)-26
Check Yes
Go to step 2.
Go to step 3.
Perform the diag-
nosis according to
DTC for LAN sys-
tem.
Replace the
VDCCM&H/U.
No
Perform the self-
diagnosis of com-
bination meter.
Replace the
VDCCM.
Go to step 4.
Repair the combi-
nation meter
assembly.