Subaru 2002 IMPREZA Service Manual page 2171

DIAGNOSTICS CHART WITH DIAGNOSIS CONNECTOR
Step
2 CHECK GROUND SHORT OF HARNESS.
1)Turn the ignition switch to OFF.
2)Disconnect all connectors from TCM.
3)Disconnect the connector from ABSCM&
H/U.
4)Measure the resistance between
ABSCM&H/U connector and chassis ground.
Connector & terminal
LHD: (B301) No. 3 — Chassis ground:
RHD: (F49) No. 3 — Chassis ground:
3 CHECK BATTERY SHORT OF HARNESS.
Measure the voltage between ABSCM&H/U
connector and chassis ground.
Connector & terminal
LHD: (B301) No. 3 (+) — Chassis ground
( − − − − ):
RHD: (F49) No. 3 (+) — Chassis ground
( − − − − ):
4 CHECK BATTERY SHORT OF HARNESS.
1)Turn the ignition switch to ON.
2)Measure the voltage between ABSCM&H/U
connector and chassis ground.
Connector & terminal
LHD: (B301) No. 3 (+) — Chassis ground
( − − − − ):
RHD: (F49) No. 3 (+) — Chassis ground
( − − − − ):
5 CHECK TCM.
1)Turn the ignition switch to OFF.
2)Connect all connectors to TCM.
3)Turn the ignition switch to ON.
4)Measure the voltage between TCM connec-
tor terminal and chassis ground.
Connector & terminal
(B55) No. 21 (+) — Chassis ground ( − − − − ):
6 CHECK AT.
7 CHECK OPEN CIRCUIT OF HARNESS.
Measure the voltage between ABSCM&H/U
connector and chassis ground.
Connector & terminal
LHD: (B301) No. 3 (+) — Chassis ground
( − − − − ):
LHD: (B301) No. 31 (+) — Chassis
ground ( − − − − ):
RHD: (F49) No. 3 (+) — Chassis ground
( − − − − ):
RHD: (F49) No. 31 (+) — Chassis ground
( − − − − ):
8 CHECK POOR CONTACT IN CONNECTORS. Is there poor contact in con-
9 CHECK ABSCM&H/U.
1)Turn the ignition switch to OFF.
2)Connect all connectors.
3)Erase the memory.
4)Perform the inspection mode.
5)Read out the DTC.
Check
Is the resistance more than 1
MΩ?
Is the voltage less than 1 V?
Is the voltage less than 1 V?
Is the voltage between 10 and
15 V?
Is the AT functioning normally? Replace the TCM. Repair the AT.
Is the voltage between 10 and
15 V?
nectors between TCM and
ABSCM&H/U?
Is the same DTC as in the cur-
rent diagnosis still being out-
put?
ABS-73
ABS (DIAGNOSTICS)
Yes
Go to step 3. Repair the har-
ness between
TCM and
ABSCM&H/U.
Go to step 4. Repair the har-
ness between
TCM and
ABSCM&H/U.
Go to step 5. Repair the har-
ness between
TCM and
ABSCM&H/U.
Go to step 7. Go to step 6.
Go to step 8. Repair the har-
ness/connector
between TCM and
ABSCM&H/U.
Repair the con- Go to step 9.
nector.
Replace the Go to step 10.
ABSCM&H/U.
<Ref. to ABS-7,
ABS Control Mod-
ule and Hydraulic
Control Unit
(ABSCM&H/U).>
No