Subaru Legacy 2005 Service Manual page 3194

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
Step
5 CHECK VDCCM&H/U POWER SUPPLY CIR-
CUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the VDCCM&H/U connector.
3) Turn the ignition switch to ON.
4) Measure the voltage between VDCCM&H/
U connector terminals.
Connector & terminal
(B310) No. 14 (+) — (B310) No. 6 (
6 CHECK ABS WHEEL SPEED SENSOR SIG-
NAL.
1) Install the ABS wheel speed sensor.
2) Prepare an oscilloscope.
3) Check the ABS wheel speed sensor. <Ref.
to ABS-15, ABS WHEEL SPEED SENSOR,
INSPECTION, Rear ABS Wheel Speed Sen-
sor.>
7 CHECK ABS WHEEL SPEED SENSOR OR
MAGNETIC ENCODER.
8 CHECK VDCCM&H/U.
1) Connect all the connectors.
2) Perform the clear memory mode.
3) Perform the inspection mode. <Ref. to
VDC(diag)-24, PROCEDURE, Inspection
Mode.>
4) Read the DTC.
9 CHECK OTHER DTC DETECTION.
Check
Is the voltage 10 — 15 V?
−
):
Does the oscilloscope indicate
the waveform pattern like
shown in the figure when the
tire is slowly turned? Does the
oscilloscope indication repeat
the waveform pattern like
shown in the figure when the
tire is slowly turned in equal
speed for more one rotation?
Are there foreign materials,
breakage or damage in the
protrusion of ABS wheel speed
sensor or magnetic encoder?
Is the same DTC displayed?
Is any other DTC displayed?
VDC(diag)-50
Yes
Go to step 8. Check the genera-
tor, battery and
VDCCM&H/U
power supply cir-
cuit.
Go to step 8. Go to step 7.
Remove dirt Go to step 8.
throughly. Also
replace the ABS
wheel speed sen-
sor or magnetic
encoder as a unit
with hub unit bear-
ing if it is broken or
damaged.
Replace the Go to step 9.
VDCCM&H/U.
<Ref. to VDC-7,
VDC Control Mod-
ule and Hydraulic
Control Unit
(VDCCM&H/U).>
Perform the diag- It results from a
nosis according to temporary noise
DTC. interference.
No