Subaru Legacy 2002 Service Manual page 2683

DIAGNOSTICS CHART WITH SELECT MONITOR
VDC (Diagnostics)
No.
1 CHECK CONTACT POINT OF MOTOR
RELAY.
1) Turn ignition switch to OFF.
2) Remove motor relay from relay box.
3) Connect battery to motor relay terminals
No. 85 and No. 86.
4) Measure resistance between motor relay
terminals.
Terminals
No. 30 — No. 87:
2 CHECK CONTACT POINT OF MOTOR
RELAY.
1) Disconnect battery from motor relay termi-
nals.
2) Measure resistance between motor relay
terminals.
Terminals
No. 30 — No. 87:
3 CHECK INPUT VOLTAGE OF RELAY BOX.
1) Disconnect connector (F89) from relay box.
2) Disconnect connector from VDCCM.
3) Turn ignition switch to ON.
4) Measure voltage between relay box con-
nector and chassis ground.
Connector & terminal
(F89) No. 2 (+) — Chassis ground (−):
4 CHECK INPUT VOLTAGE OF MOTOR
RELAY.
1) Turn ignition switch to OFF.
2) Connect connector (F89) to relay box.
3) Turn ignition switch to ON.
4) Measure voltage between relay box and
chassis ground.
Connector & terminal
Motor relay installing point No. 87 (+)
— Chassis ground (−):
5 CHECK CONDITION OF MOTOR GROUND.
Tightening torque:
32±10 N·m (3.3±1.0 kgf-m, 24±7 ft-lb)
6 CHECK VDCCM MOTOR DRIVE TERMINAL.
1) Turn ignition switch OFF.
2) Remove VDC connector cover. <Ref. to
VDC-17, REMOVE, VDCCM Connector
Cover.>
3) Connect all connectors.
4) Install motor relay.
5) Operate the ABS check sequence. <Ref. to
VDC-16, ABS Sequence Control.>
6) Measure voltage between VDCCM connec-
tor terminals.
Connector & terminal
(F87) No. 22 (+) — No. 1 (−):
7 CHECK MOTOR OPERATION.
Operate the check sequence. <Ref. to
VDC-19 VDC Sequence Control.>
8 CHECK POOR CONTACT IN CONNEC-
TORS.
Turn ignition switch to OFF.
Step
Is the resistance less than
0.5 Ω?
Is the resistance more than
1 MΩ?
Is the voltage between 10
and 15 V?
Is the voltage between 10
and 15 V?
Is the motor ground termi-
nal tightly clamped?
Does the voltage drop from
between 10 V and 13 V to
less than 1.5 V, and rise to
between 10 V and 13 V
again when carrying out
the check sequence?
Can motor revolution noise
(buzz) be heard when car-
rying out the check
sequence?
Is there poor contact in
connector between
VDCH/U, relay box and
VDCCM?
VDC-224
Check Yes
Go to step 2.
Go to step 3.
Go to step 4.
Go to step 5.
Go to step 6.
Go to step 7.
Go to step 8.
Repair connector.
No
Replace motor
relay.
Replace motor
relay.
Repair harness/
connector
between battery
and relay box,
and check fuse
SBF holder.
Replace relay
box.
Tighten the clamp
of motor ground
terminal.
Replace VDCCM.
<Ref. to VDC-9,
VDC Control Mod-
ule (VDCCM).>
Replace VDCH/U.
<Ref. to VDC-11,
Hydraulic Control
Unit (H/U).>
Go to step 9.