Subaru Legacy 2002 Service Manual page 2611

DIAGNOSTICS CHART WITH SELECT MONITOR
VDC (Diagnostics)
No.
1 CHECK IF THE WHEELS HAVE TURNED
FREELY FOR A LONG TIME.
2 CHECK TIRE SPECIFICATIONS.
3 CHECK WEAR OF TIRE.
4 CHECK TIRE PRESSURE.
5 CHECK INSTALLATION OF ABS SENSOR.
Tightening torque:
32±10 N·m (3.3±1.0 kgf-m, 24±7 ft-lb)
6 CHECK ABS SENSOR GAP.
Measure tone wheel to pole piece gap over
entire perimeter of the wheel.
Specifications
Front wheel
0.3 — 0.8 mm (0.012 — 0.031 in)
Rear wheel
0.44 — 0.94 mm (0.0173 — 0.0370 in)
7 CHECK OSCILLOSCOPE.
8 CHECK ABS SENSOR SIGNAL.
1) Raise all four wheels of ground.
2) Turn ignition switch OFF.
3) Remove VDCCM connector cover. <Ref. to
VDC-17, REMOVE, VDCCM Connector
Cover.>
4) Connect the oscilloscope to the connector.
5) Turn ignition switch ON.
6) Rotate wheels and measure voltage at
specified frequency. <Ref. to ABS-15,
WAVEFORM, Control Module I/O Signal.>
NOTE:
When this inspection is completed, the
VDCCM sometimes stores the DTC 29.
Connector & terminal
(F49) No. 14 (+) — No. 15 (−) (Front
RH):
(F49) No. 49 (+) — No. 19 (−) (Front
LH):
(F49) No. 18 (+) — No. 46 (−) (Rear
RH):
(F49) No. 16 (+) — No. 17 (−) (Rear LH):
Step
Check if the wheels have
been turned freely for more
than one minute, such as
when the vehicle is jacked-
up, under full-lock corner-
ing or when tire is not in
contact with road surface.
Are the tire specifications
correct?
Is the tire worn exces-
sively?
Is the tire pressure correct? Go to step 5.
Are the ABS sensor instal-
lation bolts tightened
securely?
Is the gap within the speci-
fications?
Is an oscilloscope avail-
able?
Is oscilloscope pattern
smooth, as shown in fig-
ure?
VDC-152
Check Yes
The VDC is nor-
mal. Erase the
diagnostic trouble
code.
NOTE:
When the wheels
turn freely for a
long time, such as
when the vehicle
is towed or
jacked-up, or
when steering
wheel is continu-
ously turned all
the way, this
trouble code may
sometimes occur.
Go to step 3.
Replace tire.
Go to step 6.
Go to step 7.
Go to step 8.
Go to step 12.
No
Go to step 2.
Replace tire.
Go to step 4.
Adjust tire pres-
sure.
Tighten ABS sen-
sor installation
bolts securely.
Adjust the gap.
NOTE:
Adjust the gap
using spacer (Part
No. 26755AA000).
If spacers cannot
correct the gap,
replace worn sen-
sor or worn tone
wheel.
Go to step 9.
Go to step 9.