Subaru 2002 IMPREZA Service Manual page 317

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
Check
s the voltage more than 8 V?
s
the value more than 2.3 A?
Step
CHECK OUTPUT SIGNAL FROM ECM.
1)Turn the ignition switch to ON.
2)Measure the voltage between ECM connec-
tor and chassis ground.
Connector & terminal
(8137) No. 4 (+)
-
Chassis ground
( - ) I
(8137) No. 5 (+)
-
Chassis ground ( - ) :
CHECK FRONT OXYGEN ( N F ) SENSOR
HEATER CURRENT.
1)Turn the ignition switch to OFF.
2)Repair the battery short circuit in harness
between ECM and front oxygen (NF) sensor
connector.
3)Turn the ignition switch to ON.
4)Read the data of front oxygen (NF) sensor
heater current using Subaru Select Monitor or
the OBD-ll general scan tool.
NOTE:
*Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE. <Ref.
tq
EN(D0HC TURBO)-38, Subaru Select Mon-
itor.>
*OED41 general scan tool
For detailed operation procedure, refer to the
OBD-ll General Scan Tool Instruction Manual.
CHECK OUTPUT SIGNAL FROM ECM.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(8137) No. 4 (+)
-
Chassis ground (-):
(8137) No. 5 (+)
-
Chassis ground (-):
Yes
Go to step 3.
Replace the ECM.
<Ref. to FU(D0HC
Engine Control
TURBO)-47,
Module.>
ige meter? oxygen (NF) sen-
sor connector.
No
i o
to
step 2.
END
END
EN( DOHC TU RB0)-93