Subaru Legacy 2004 Service Manual page 3005

ABS Warning Light / Brake Warning Light Illumination Pattern
ABS (DIAGNOSTICS)
Step
1 CHECK INSTALLATION OF ABSCM&H/U
CONNECTOR.
1) Turn the ignition switch to OFF.
2) Check that the ABSCM&H/U connector is
inserted to ABSCM&H/U until the clamp locks
onto it.
2 READ DTC.
Read the DTC. <Ref. to ABS(diag)-25, Read
Diagnostic Trouble Code (DTC).>
3 CHECK THE BRAKE FLUID AMOUNT.
Check the amount of brake fluid in the reser-
voir tank of master cylinder.
4 CHECK BRAKE FLUID LEVEL SWITCH.
1) Disconnect the level switch connector (B16)
from master cylinder.
2) Measure the resistance of master cylinder
terminals.
Terminals
No. 1 — No. 2:
5 CHECK PARKING BRAKE SWITCH.
1) Disconnect the connector (R4) from park-
ing brake switch.
2) Release the parking brake.
3) Measure the resistance between parking
brake switch terminal and chassis ground.
6 CHECK GROUND SHORT OF HARNESS.
1) Disconnect the connector (i10) from combi-
nation meter.
2) Measure the resistance between combina-
tion meter connector and chassis ground.
Connector & terminal
(i10) No. 8 — Chassis ground:
7 CHECK HARNESS.
1) Disconnect the connector (B301) from
ABSCM&H/U.
2) Disconnect the connector (i10) from the
combination meter.
3) Measure the resistance between
ABSCM&H/U connector and combination
meter connector.
Connector & terminal
(B301) No. 8 — (i10) No. 7:
8 CHECK POOR CONTACT IN CONNECTOR.
Check poor contact in all connectors.
9 CHECK ABSCM.
1) Connect the connector to the ABSCM&H/U.
2) Turn the ignition switch to ON.
3) Measure the resistance between combina-
tion meter connector and chassis ground.
Connector & terminal
(i10) No. 7 — Chassis ground:
Check
Is the connector correctly
inserted?
Is DTC displayed?
Is the amount of brake fluid
between the lines of MAX and
MIN?
Is the resistance more than 1
M&?
Is the resistance more than 1
M&?
Is the resistance more than 1
M&?
Is the resistance less than 0.5
&?
Is there poor contact?
Is the resistance less than 0.5
&?
ABS(diag)-38
Yes
Go to step 2. Insert the
ABSCM&H/U con-
nector until the
clamp locks onto
it.
Perform the diag- Go to step 3.
nosis according to
DTC.
Go to step 4. Replenish brake
fluid to the speci-
fied value.
Go to step 5. Replace the mas-
ter cylinder.
Go to step 6. Replace the park-
ing brake switch.
Go to step 7. Repair the har-
ness connector
between combina-
tion meter and
parking brake
switch.
Go to step 8. Repair harness
between
ABSCM&H/U and
combination meter
connector.
Repair the con- Go to step 9.
nector.
Check the combi- Replace the
nation meter. ABSCM only.
<Ref. to ABS-8,
REPLACEMENT,
ABS Control Mod-
ule and Hydraulic
Control Unit
(ABSCM&H/U).>
No