Subaru 2004 LEGACY, Service Manual

Page: 443 / 609

VDC(diag)-121
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK LATERAL G SENSOR OUTPUT.
1) Park the vehicle on a level surface.
2) Select {Current Data Display & Save} in
Subaru Select Monitor.
3) Read the lateral G sensor output displayed
on display. Is the indicated reading on the
monitor display
−
1.5 — 1.5
m/s
2
?
Go to step 2. Go to step 3.
2 CHECK POOR CONTACT IN CONNECTORS.
Turn the ignition switch to OFF. Is there poor contact in con-
nector between VDCCM&H/U
and yaw rate & lateral G sen-
sor? Repair the con-
nector. Go to step 10.
3 CHECK YAW RATE & LATERAL G SENSOR
POWER SUPPLY.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from yaw rate &
lateral G sensor.
3) Turn the ignition switch to ON.
4) Measure the voltage between yaw rate &
lateral G sensor and chassis ground.
Connector & terminal
(B230) No. 3 (+) — Chassis ground (
−
):
Is the voltage 10 — 15 V? Go to step 6. Go to step 4.
4 CHECK OUTPUT VOLTAGE OF VDCCM&H/
U.
Measure the voltage between VDCCM&H/U
and chassis ground.
Connector & terminal
(B310) No. 30 (+) — Chassis ground (
−
):
Is the voltage 10 — 15 V? Repair the har-
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U. Go to step 5.
5 CHECK POOR CONTACT IN CONNECTORS Is there poor contact in con-
nector?
Correct or replace
the connector. Go to step 10.
6 CHECK OPEN CIRCUIT IN LATERAL G SEN-
SOR OUTPUT HARNESS.
1) Disconnect the connector from yaw rate &
lateral G sensor.
2) Disconnect the connector from VDCCM&H/
U.
3) Measure the resistance between
VDCCM&H/U and yaw rate & lateral G sensor.
Connector & terminal
(B310) No. 3 — (B230) No. 5:
Is the resistance less than 0.5
Ω
?
Go to step 7. Repair the har-
ness connector
between yaw rate
& lateral G sensor
and VDCCM&H/U.
7 CHECK GROUND SHORT CIRCUIT FOR
YAW RATE & LATERAL G SENSOR HAR-
NESS.
Measure the resistance between VDCCM&H/U
connector and chassis ground.
Connector & terminal
(B310) No. 3 — Chassis ground:
Is the resistance more than 1
M
Ω
?
Go to step 8. Repair the har-
ness connector
between yaw rate
& lateral G sensor
and VDCCM&H/U.
8 CHECK LATERAL G SENSOR.
1) Turn the ignition switch to OFF.
2) Remove the yaw rate & lateral G sensor
from vehicle.
3) Connect the connector to the yaw rate &
lateral G sensor.
4) Connect the connector to VDCCM&H/U.
5) Turn the ignition switch to ON.
6) Measure the voltage between yaw rate &
lateral G sensor connector terminals.
Connector & terminal
(B230) No. 5 (+) — No. 6 (
−
):
Is the voltage 2.35 — 2.65 V
when yaw rate & lateral G sen-
sor is on level? Go to step 9. Replace the yaw
rate & lateral G
sensor.