Subaru Legacy 2004 Service Manual page 3122

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK POOR CONTACT IN CONNECTOR.
Check if there is poor contact between
VDCCM&H/U and ABS wheel speed sensor.
2 CHECK HARNESS CONNECTOR BETWEEN
VDCCM&H/U AND ABS WHEEL SPEED
SENSOR.
1) Disconnect the connector (B310) from
VDCCM&H/U.
2) Disconnect the connector from ABS wheel
speed sensor.
3) Measure the resistance between
VDCCM&H/U connector and ABS wheel
speed sensor connector.
Connector & terminal
DTC C0021
(B310) No. 22 — (B6) No. 1:
(B310) No. 21 — (B6) No. 2:
DTC C0023
(B310) No. 41 — (B15) No. 1:
(B310) No. 25 — (B15) No. 2:
DTC C0025
(B310) No. 23 — (R72) No. 1:
(B310) No. 38 — (R72) No. 2:
DTC C0027
(B310) No. 24 — (R73) No. 1:
(B310) No. 40 — (R73) No. 2:
3 CHECK GROUND SHORT OF HARNESS.
Measure the resistance between VDCCM&H/U
connector and chassis ground.
Connector & terminal
DTC C0021
(B310) No. 21 — Chassis ground:
DTC C0023
(B310) No. 25 — Chassis ground:
DTC C0025
(B310) No. 38 — Chassis ground:
DTC C0027
(B310) No. 40 — Chassis ground:
4 CHECK ABS WHEEL SPEED SENSOR POW-
ER SUPPLY CIRCUIT.
1) Connect the VDCCM&H/U connector.
2) Turn the ignition switch to ON.
3) Measure the voltage between ABS wheel
speed sensor connector and chassis ground.
Connector & terminal
DTC C0021
(B6) No. 1 (+) — Chassis ground (
DTC C0023
(B15) No. 1 (+) — Chassis ground (
DTC C0025
(R72) No. 1 (+) — Chassis ground (
DTC C0027
(R73) No. 1 (+) — Chassis ground (
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
Check
Is there poor contact?
Is the resistance less than 0.5
&?
Is the resistance more than 1
M&?
Is the voltage 5 — 16 V?
#
):
#
):
#
):
#
):
VDC(diag)-49
Yes
Repair the con- Go to step 2.
nector.
Go to step 3. Repair the har-
ness connector
between
VDCCM&H/U and
ABS wheel speed
sensor.
Go to step 4. Repair the har-
ness connector
between
VDCCM&H/U and
ABS wheel speed
sensor.
Go to step 6. Go to step 5.
No