Subaru 2002 IMPREZA Service Manual page 595

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
Step
CHECK INPUT SIGNAL FOR ECM.
1)Turn the ignition switch to ON.
2)Measure the voltage between ECM and
chassis ground.
Connector & terminal
(8134)
No.
18 (+)
-
Chassis ground (-) :
CHECK INPUT SIGNAL FOR ECM.
Measure the voltage between ECM and chas-
sis ground.
Connector & terminal
CHECK POOR CONTACT.
Check poor contact in ECM connector.
(8134) No. 18 (+)
-
Chassis ground ( - ) :
CHECK HARNESS BETWEEN ECM AND
TCM CONNECTOR.
1)Turn the ignition switch to OFF.
2)Disconnect the connectors from ECM and
TCM.
3)Measure the resistance of harness between
ECM and TCM connector.
Connector & i terminal
( 8 134)
NO.
18
-
(856)
NO.
4:
CHECK HARNESS BETWEEN ECM AND
TCM CONNECTOR.
Measure the resistance of harness between
ECM and chassis ground.
Connector & terminal
(8134)
No.
18
-
Chassis ground:
CHECK POOR CONTACT.
Check poor contact in TCM connector.
Check
Is the voltage more than 4.5 V?
Is the voltage more than 10 V?
Is there poor contact in ECM
Zonnector?
Is the resistance less than
1
n?
Is the resistance less than 10
n?
Is there poor contact in TCM
connector?
Yes
Go to step 2.
Repair battery
short circuit in har-
ness between
ECM and TCM
connector.
Repair poor con-
tact in ECM con-
nector.
Go to step 5.
Repair ground
short circuit in har-
ness between
ECM and TCM
connector.
Repair poor con-
tact in TCM con-
nector.
No
30 to step 4.
30 to step 3 .
3eplace the ECM.
:Ref. to FU(D0HC
Engine Control
Module.>
3epair open circuii
n harness
ietween ECM and
TCM connector.
rURBO)-47,
30 to step
6.
3eplace the TCM.
:Ref. to AT-45,
rransmission Con-
:rol Module
:TCM).>
EN(D0HC TURBO)-371