Subaru Legacy 2004 Service Manual page 3123

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 VDCCM&H/U.
1) Connect all the connectors.
2) Erase the memory.
3) Perform the inspection mode. <Ref. to
VDC(diag)-23, PROCEDURE, Inspection
Mode.>
4) Read the DTC.
8 CHECK OTHER DTC DETECTION.
Check
Is the voltage 10 — 15 V?
#
):
Is waveform pattern same as
shown in the figure.
Is the same DTC displayed?
Is any other DTC displayed?
VDC(diag)-50
Yes
Go to step 7. Check the genera-
tor, battery and
VDCCM&H/U
power supply cir-
cuit.
Go to step 7. Replace the ABS
wheel speed sen-
sor.
Replace the Go to step 8.
VDCCM&H/U.
<Ref. to VDC-7,
VDC Control Mod-
ule & Hydraulic
Control Unit
(VDCCM&H/U).>
Perform the diag- It results from a
nosis according to temporary noise
DTC. interference.
No