Subaru Legacy 2004 Service Manual page 3194

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
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.
2 CHECK POOR CONTACT IN CONNECTORS.
Turn the ignition switch to OFF.
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 (
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 (
5 CHECK POOR CONTACT IN CONNECTORS Is there poor contact in con-
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:
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:
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 (
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
Is the indicated reading on the
monitor display #1.5 — 1.5
2
m/s ?
Is there poor contact in con-
nector between VDCCM&H/U
and yaw rate & lateral G sen-
sor?
Is the voltage 10 — 15 V?
#
):
Is the voltage 10 — 15 V?
#
):
nector?
Is the resistance less than 0.5
&?
Is the resistance more than 1
M&?
Is the voltage 2.35 — 2.65 V
when yaw rate & lateral G sen-
sor is on level?
#
):
VDC(diag)-121
Check Yes
Go to step 2.
Repair the con-
nector.
Go to step 6.
Repair the har-
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U.
Correct or replace
the connector.
Go to step 7.
Go to step 8.
Go to step 9.
No
Go to step 3.
Go to step 10.
Go to step 4.
Go to step 5.
Go to step 10.
Repair the har-
ness connector
between yaw rate
& lateral G sensor
and VDCCM&H/U.
Repair the har-
ness connector
between yaw rate
& lateral G sensor
and VDCCM&H/U.
Replace the yaw
rate & lateral G
sensor.