Subaru LEGACY 2003 Service Manual page 75

DIAGNOSTICS CHART WITH DIAGNOSIS CONNECTOR
Step
1 CHECK INPUT VOLTAGE OF ABSCM&H/U.
1) Turn ignition switch to OFF.
2) Disconnect connector from ABSCM&H/U.
3) Turn ignition switch to ON.
4) Measure voltage between ABSCM&H/U
connector and chassis ground.
Connector & terminal
(F49) No. 25 (+) — Chassis ground ( − − − − ):
Is the measured value within the specified
range?
2 CHECK GROUND CIRCUIT OF MOTOR.
1) Turn ignition switch to OFF.
2) Measure resistance between ABSCM&H/U
connector and chassis ground.
Connector & terminal
(F49) No. 26 — Chassis ground:
Is the measured value less than the speci-
fied value?
3 CHECK INPUT VOLTAGE OF ABSCM&H/U.
1) Run the engine at idle.
2) Measure voltage between ABSCM&H/U
connector and chassis ground.
Connector & terminal
(F49) No. 1 (+) — Chassis ground ( − − − − ):
Is the measured value within the specified
range?
4 CHECK GROUND CIRCUIT OF ABSCM&H/U.
1) Turn ignition switch to OFF.
2) Measure resistance between ABSCM&H/U
connector and chassis ground.
Connector & terminal
(F49) No. 23 — Chassis ground:
Is the measured value less than the speci-
fied value?
5 CHECK MOTOR OPERATION.
Operate the sequence control. <Ref. to ABS-
9, ABS Sequence Control.>
NOTE:
Use the diagnosis connector to operate the se-
quence control.
Can motor revolution noise (buzz) be heard
when carrying out the sequence control?
6 CHECK POOR CONTACT IN CONNECTORS.
Turn ignition switch to OFF.
Is there poor contact in connector between
generator, battery and ABSCM&H/U?
7 CHECK ABSCM&H/U.
1) Connect all connectors.
2) Erase the memory.
3) Perform inspection mode.
4) Read out the DTC.
Is the same DTC still being output?
8 CHECK ANY OTHER DTC APPEARANCE.
Are other DTC being output?
Value
10 - 15 V
0.5 Ω
10 - 15 V
0.5 Ω
Operating sound is produced.
There is no poor contact.
Same DTC is not indicated.
Other DTC is not indicated.
ABS-73
ABS (DIAGNOSTICS)
Yes
Go to step 2. Repair harness/
connector
between battery
and ABSCM&H/U
and check fuse
SBF-holder.
Go to step 3. Repair
ABSCM&H/U
ground harness.
Go to step 4. Repair harness
connector
between battery,
ignition switch and
ABSCM&H/U.
Go to step 5. Repair
ABSCM&H/U
ground harness.
Go to step 6. Replace
ABSCM&H/U.
<Ref. to ABS-6,
ABS Control Mod-
ule and Hydraulic
Control Unit
(ABSCM&H/U).>
Go to step 7. Repair connector.
Go to step 8. Replace
ABSCM&H/U.
<Ref. to ABS-6,
ABS Control Mod-
ule and Hydraulic
Control Unit
(ABSCM&H/U).>
A temporary poor Proceed with the
contact. diagnosis corre-
sponding to the
DTC.
No