Subaru Legacy 2003 Service Manual page 508

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Step
1 CHECK CURRENT DATA.
1) Start engine.
2) Read the data of intake manifold absolute
pressure signal using Subaru Select Moni-
tor or OBD-II general scan tool.
Does the measured value exceed the spec-
ified value?
NOTE:
•Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE".
<Ref. to EN(H4SO)-32, Subaru Select Moni-
tor.>
•OBD-II general scan tool
For detailed operation procedures, refer to the
OBD-II General Scan Tool Instruction Manual.
2 CHECK INPUT SIGNAL FOR ECM.
Measure voltage between ECM connector and
chassis ground.
Connector & terminal
(B135) No. 3 (+) — Chassis ground ( − − − − ):
Does the measured value exceed the specified
value?
3 CHECK INPUT SIGNAL FOR ECM.
Measure voltage between ECM connector and
chassis ground.
Connector & terminal
(B135) No. 3 (+) — Chassis ground ( − − − − ):
Does the measured value exceed the specified
value by shaking harness and connector of
ECM while monitoring the value with voltage
meter?
4 CHECK INPUT SIGNAL FOR ECM.
Measure voltage between ECM connector and
chassis ground.
Connector & terminal
(B135) No. 15 (+) — Chassis ground ( − − − − ):
Is the measured value less than the specified
value?
5 CHECK INPUT SIGNAL FOR ECM. (USING
SUBARU SELECT MONITOR.)
Read data of atmospheric absolute pressure
signal using Subaru Select Monitor.
Does the measured value exceed the specified
value by shaking harness and connector of
ECM while monitoring the value with Subaru
Select Monitor?
NOTE:
•Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE".
<Ref. to EN(H4SO)-32, Subaru Select Moni-
tor.>
Value
119.5 kPa (896.5 mmHg,
35.29 inHg)
4.5 V
4.5 V
0.2 V
13.3 kPa (100 mmHg, 3.94
inHg)
EN(H4SO)-111
ENGINE (DIAGNOSTICS)
Yes
Go to step 9. Go to step 2.
Go to step 4. Go to step 3.
Repair poor con- Contact SUBARU
tact in ECM con- distributor service.
nector.
NOTE:
Inspection by DTM
is required,
cause
cause is deteriora-
tion of
parts.
Go to step 6. Go to step 5.
Repair poor con- Go to step 6.
tact in ECM con-
nector.
No
be-
probable
multiple