Subaru IMPREZA 2002 Service Manual page 257

a
DIAGNOSTICS CHART WITH DIAGNOSIS CONNECTOR
ABS (DIAGNOSTICS)
Step
CHECKGENERATOR.
1)Start the engine.
2)ldling after warm-up.
3)Measure the voltage between generator B
terminal and chassis ground.
Terminal
Generator 8 terminal
-
Chassis ground:
CHECK BATTERY TERMINAL.
Turn the ignition switch to OFF.
CHECK INPUT VOLTAGE OF RELAY HOLD-
ER.
1)Turn the ignition switch to OFF.
2)Remove the fuse.
3)Measure the voltage between ABS relay
connector and chassis ground.
Connector & terminal
(8225)
No.
5 (+)
-
Chassis ground ( - ) :
CHECK RELAY HOLDER.
CHECK INPUT VOLTAGE OF ABS RELAY.
1)lnstall the fuse.
2)Remove the ABS relay.
3)Turn the ignition switch to ON.
4)Measure the voltage between ABS relay
connector and chassis ground.
Connector & terminal
(8264) No. 2 (+)
-
Chassis ground (-):
CHECK INPUT VOLTAGE OF ABS RELAY.
Measure the voltage between ABS relay con-
nector and chassis ground.
Connector & terminal
(8264)
No.
1 (+)
-
Chassis ground (-):
CHECK GROUND CIRCUIT OF ABS RELAY.
1)Turn the ignition switch to OFF.
2)Measure the resistance between ABS relay
connector and chassis ground.
Connector & terminal
(8264)
No.
3 (+)
-
Chassis ground:
CHECK ABS RELAY.
1)Connect the battery to ABS relay terminal
No. 1 and 3.
2)Measure the resistance between ABS relay
terminals.
CHECK INPUT VOLTAGE OF ABSCM&H/U.
1)Disconnect the connector from ABSCM&
H/U.
2)Run the engine at idle.
3)Measure the voltage between ABSCM&H/U
connector and chassis grou.nd.
Connector & terminal
(F49) No. 1 (+)
-
Chassis ground (-):
CHECK GROUND CIRCUIT OF ABSCM&H/U.
1)Turn the ignition switch to OFF.
2)Measure the resistance between
ABSCM&H/U connector and chassis ground.
1
Connector & terminal
(F49)
No.
23
-
Chassis ground:
Check
s
the voltage between 10 and
7 V?
ire the positive and negative
battery terminals tightly
ilamped?
s the voltage more than 10 V?
s the fuse blown out?
s the voltage more than 10 V?
s the voltage more than 10 V?
s the resistance less than 5
2?
s
the resistance less than 10
a?
s the voltage between 10 and
I7 V?
s the resistance less than 0.5
3?
Yes
30 to step 2.
30 to step 3 .
30 to step 4.
3eplace the fuse.
30 to step 6.
30
to step 7.
30
to step 8.
30
to step 9.
So to step 10.
Go to step 11.
No
qepair the genera-
:or. <Ref. to SC-
13, Generator.>
Tighten the clamp
2f
terminal.
Repair open circuit
n harness
3etween battery
and Relay holder
:onnector.
Go to step 5.
Repair open circuit
in harness
between battery
and Relay holder
connector.
Repair harness
connector
between battery,
ignition switch and
ABS relay.
Repair open circuit
between ABS
relay and chassis
ground.
Replace the ABS
relay.
Repair harness
connector
between battery,
ignition switch and
ABSCM&H/U.
Repair the
ABSCM&H/U
ground harness.
ABS-71