Subaru IMPREZA 2002 Service Manual page 585

I
DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
Step
1
CHECK CURRENT DATA.
1)Start the engine.
2)Read the data of intake manifold absolute
pressure signal using Subaru Select Monitor or
OBD-I1 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-I1 general scan tool
For detailed operation procedures, refer to the
OBD-ll General Scan Tool Instruction Manual.
CHECK INPUT SIGNAL FOR ECM.
Measure the voltage between ECM connector
and chassis ground.
2
Connector & terminal
(B 136) No. 15 (+)
-
Chassis ground ( - ) :
CHECK INPUT SIGNAL FOR ECM.
Measure the voltage between ECM connector
and chassis ground.
3
Connector & terminal
(8136) No. 15 (+)
-
Chassis ground ( - ) :
4
CHECK INPUT SIGNAL FOR ECM.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(8136) No. 29 (+)
-
Chassis ground
( - ) I
CHECK INPUT SIGNAL FOR ECM. (USING
SUBARU SELECT MONITOR.)
Read the data of atmospheric absolute pres-
sure signal using Subaru Select Monitor.
NOTE:
*Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE". <Ref.
to EN(S0HC)-32, Subaru Select Monitor.>
CHECK HARNESS BETWEEN ECM AND
PRESSURE SENSOR CONNECTOR.
1)Turn the ignition switch to OFF.
2)Disconnect the connector from atmospheric
pressure sensor.
3)Turn the ignition switch to ON.
4)Measure the voltage between atmospheric
pressure sensor connector and engine ground
5
6
Connector & terminal
(82) No. 3 (+)
-
Engine ground (-):
Check
s
the value more than 140 kPa
1,050 mmHg, 41 3 4 inHg)?
s the voltage more than 4.5 V'?
Ioes the voltage change more
han 4.5 V by shaking harness
md connector of ECM while
nonitoring the value with volt-
ige meter?
s the voltage less than 0.2 V?
loes the value change more
han 0 kPa (0 mmHg, 0 inHg)
iy shaking harness and con-
lector of ECM while monitor-
ng the value with Subaru
;elect monitor?
s the voltage more than 4.5 V'
Yes
; o to step 10.
; o to step 4.
Iepair poor con-
x t in ECM con-
lector.
30 to step
6.
3epair poor con-
act in ECM con-
lector.
; o to step 7.
No
30 to step 2.
; o to step 3.
:ontact with SOA
distributor) ser-
rice.
JOTE:
nspection by DTh
s required, be
:awe probabli
:ause is deteriora
ion of multipli
)arts.
30 to step 5.
; o to step
6.
3epair harness
ind connector.
IOTE:
n this case, repai
he following:
b
Open circuit in
iarness between
X M and pressurc
sensor connector
1
Poor contact in
oint connector
18122)
EN(S0HC)-261