Subaru IMPREZA 2002 Service Manual page 447

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
Yes
30 to step 2.
3epair battery
short circuit in har-
less between
ICM and engine
:oolant tempera-
ure sensor con-
lector.
Step
CHECK CURRENT DATA.
1)Start the engine.
2)Read the data of engine coolant temperature
sensor signal using Subaru Select Monitor or
OBD-ll general scan tool.
NOTE:
*Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE. <Ref.
to EN(S0HC)-32, Subaru Select Monitor.>
*OBD-ll general scan
tool
For detailed operation procedures, refer to the
OBD-ll General Scan Tool Instruction Manual.
No
Repair poor con-
tact.
NOTE:
In this case, repai
the following:
Poor contact in
engine coolant
temperature sen-
sor
Poor contact in
ECM
Poor contact in
coupling connectoi
Poor contact in
joint connector
(B122)
Go to step 3.
(B21)
CHECK HARNESS BETWEEN ENGINE
COOLANT TEMPERATURE SENSOR AND
ECM CONNECTOR.
1)Turn the ignition switch to OFF.
2)Disconnect the connector from engine cool-
ant temperature sensor.
3)Measure the voltage between engine coolant
temperature sensor connector and engine
ground.
Connector
&
terminal
(€8) No. 1 (+)
-
Engine ground
(-):
CHECK HARNESS BETWEEN ENGINE
COOLANT TEMPERATURE SENSOR AND
ECM CONNECTOR.
1)Turn the ignition switch to ON.
2)Measure the voltage between engine coolant
temperature sensor connector and engine
ground.
Connector
&
terminal
(€8)
No. 1 (+)
-
Engine ground
( - ) :
CHECK HARNESS BETWEEN ENGINE
COOLANT TEMPERATURE SENSOR AND
ECM CONNECTOR.
Measure the voltage between engine coolant
temperature sensor connector and engine
ground.
Connector
&
terminal
(€8) No. 1 (+)
-
Engine ground
( - ) :
Check
s the value less than -40°C (-
IOOF)?
s the voltage more than IO V?
s
the voltage more than 10
V?
s
the voltage more than 4
V?
3epair battery
;hort circuit in har-
less between
ICM and engine
:oolant tempera-
ure sensor con-
lector.
30 to step
5.
Go to step 4.
r
I
Repair harness
and connector.
NOTE:
In this case, repai
the following:
Open circuit in
harness between
ECM and engine
coolant tempera-
ture sensor con-
nector
Poor contact in
engine coolant
temperature sen-
sor connector
Poor contact in
ECM connector
Poor contact in
coupling connectoi
Poor contact in
joint connector
(B122)
(B21)
EN(S0HC)-123