Subaru 2002 IMPREZA Service Manual page 2167

DIAGNOSTICS CHART WITH DIAGNOSIS CONNECTOR
Step
1 CHECK GENERATOR.
1)Start the engine.
2)Idle after warm-up.
3)Measure the voltage between generator B
terminal and chassis ground.
Terminal
Generator B terminal (+) — Chassis
ground ( − − − − ):
2 CHECK BATTERY TERMINAL.
Turn the ignition switch to OFF.
3 CHECK RELAY HOLDER.
4 CHECK INPUT VOLTAGE OF RELAY HOLD-
ER.
1)Turn the ignition switch to OFF.
2)Remove the relay holder fuse.
3)Measure the voltage between ABS relay
connector and chassis ground.
Connector & terminal
LHD:
(B225) No. 5 (+) — Chassis ground ( − − − − ):
RHD:
(B225) No. 3 (+) — Chassis ground ( − − − − ):
5 CHECK INPUT VOLTAGE OF ABS RELAY.
1)Install 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
(B264) No. 2 (+) — Chassis ground ( − − − − ):
6 CHECK INPUT VOLTAGE OF ABS RELAY.
Measure the voltage between ABS relay con-
nector and chassis ground.
Connector & terminal
(B264) No. 1 (+) — Chassis ground ( − − − − ):
7 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
(B264) No. 3 — Chassis ground:
8 CHECK ABS RELAY.
1)Connect the battery to ABS relay terminal
No. 1 and 3.
2)Measure the resistance between ABS relay
terminals.
9 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 ground.
Connector & terminal
LHD: (B301) No. 1 (+) — Chassis ground
( − − − − ):
RHD: (F49) No. 1 (+) — Chassis ground
( − − − − ):
Check
Is the voltage between 10 and
17 V?
Are the positive and negative
battery terminals tightly
clamped?
Is the fuse blown out?
Is the voltage more than 10 V? Go to step 5.
Is the voltage more than 10 V? Go to step 6.
Is the voltage more than 10 V? Go to step 7.
Is the resistance less than 5
Ω?
Is the resistance less than 10
Ω?
Is the voltage between 10 and
17 V?
ABS-69
ABS (DIAGNOSTICS)
Yes
Go to step 2. Repair the genera-
tor. <Ref. to SC-
14, Generator.>
Go to step 4. Tighten the clamp
of terminal.
Replace the fuse. Go to step 4.
Repair the open
circuit in harness
between battery
and relay holder
connector.
Repair the open
circuit in harness
between battery
and relay holder
connector.
Repair the har-
ness connector
between battery,
ignition switch and
ABS relay.
Go to step 8. Repair the open
circuit between
ABS relay and
chassis ground.
Go to step 9. Replace the ABS
relay.
Go to step 10. Repair the har-
ness connector
between battery,
ignition switch and
ABSCM&H/U.
No