Power; Signal - Subaru Legacy 2004 Service Manual

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK YAW RATE & LATERAL G SENSOR
POWER SUPPLY.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from the 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 (
2 CHECK OUTPUT VOLTAGE OF VDCCM&H/
U.
Measure the voltage between VDCCM&H/U
and chassis ground.
Connector & terminal
(B310) No. 30 (+) — Chassis ground (
3 CHECK POOR CONTACT IN CONNECTORS. Is there poor contact in con-
4 CHECK GROUND CIRCUIT OF YAW RATE &
LATERAL G SENSOR.
Measure the resistance between yaw rate &
lateral G sensor and chassis ground.
Connector & terminal
(B230) No. 6 — Chassis ground:
5 CHECK GROUND CIRCUIT FOR VDCCM&H/
U.
Measure the resistance between VDCCM&H/U
and chassis ground.
Connector & terminal
(B310) No. 16 — Chassis ground:
6 CHECK POOR CONTACT IN CONNECTORS. Is there poor contact in con-
7 CHECK YAW RATE & LATERAL G SENSOR
HARNESS.
1) Disconnect the connector from VDCCM&H/
U.
2) Measure the resistance between
VDCCM&H/U and yaw rate & lateral G sensor.
Connector & terminal
(B310) No. 28 — (B230) No. 4:
8 CHECK GROUND SHORT OF HARNESS.
Measure the resistance between VDCCM&H/U
connector and chassis ground.
Connector & terminal
(B310) No. 28 — Chassis ground:
9 CHECK YAW RATE & LATERAL G SENSOR.
1) Connect all the connectors.
2) Turn the ignition switch to ON.
3) Check the signal pattern of oscilloscope
between VDCCM&H/U connector terminals.
<Ref. to VDC(diag)-15, WAVEFORM, MEA-
SUREMENT, Control Module I/O Signal.>
Connector & terminal
(B310) No. 2 — No. 16:
(B310) No. 28 — No. 16:
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
Check
Is the voltage 10 — 15 V?
#
):
Is the voltage 10 — 15 V?
#
):
nector?
Is the resistance less than 0.5
&?
Is the resistance less than 0.5
&?
nector?
Is the resistance less than 0.5
&?
Is the resistance more than 1
M&?
Is the oscilloscope pattern the
same waveform as shown in
the figure?
VDC(diag)-109
Yes
Go to step 4. Go to step 2.
Repair the har- Go to step 3.
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U.
Correct or replace Go to step 10.
the connector.
Go to step 7. Go to step 5.
Repair the har- Go to step 6.
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U.
Correct or replace Go to step 10.
the connector.
Go to step 8. Repair the har-
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U.
Go to step 9. Repair the har-
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U.
Go to step 10. Replace the yaw
rate & lateral G
sensor.
No