Subaru FORESTER 2001 Service Manual page 121

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
1 CHECK CURRENT DATA.
1) Start engine.
2) Read the data of intake manifold absolute
pressure signal using Subaru Select Monitor
or OBD-II general scan tool.
NOTE:
¼ Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE".
<Ref. to EN(DOHC TURBO)-36, Subaru
Select Monitor.>
¼ 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. 9 (+) — Chassis ground (−):
3 CHECK INPUT SIGNAL FOR ECM.
Measure voltage between ECM connector
and chassis ground.
Connector & terminal
(B135) No. 9 (+) — Chassis ground (−):
4 CHECK INPUT SIGNAL FOR ECM.
Measure voltage between ECM connector
and chassis ground.
Connector & terminal
(B135) No. 8 (+) — Chassis ground (−):
5 CHECK HARNESS BETWEEN ECM AND
PRESSURE SENSOR CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from pressure sen-
sor.
3) Turn ignition switch to ON.
4) Measure voltage between pressure sensor
connector and engine ground.
Connector & terminal
(E21) No. 3 (+) — Engine ground (−):
6 CHECK HARNESS BETWEEN ECM AND
PRESSURE SENSOR CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from ECM.
3) Measure resistance of harness between
ECM and pressure sensor connector.
Connector & terminal
(B135) No. 8 — (E21) No. 1:
Step
Is the value more than 282
kPa (2,121 mmHg, 83.50
inHg)?
Is the voltage more than
4.5 V?
Does the voltage change
more than 4.5 V by shaking
harness and connector of
ECM while monitoring the
value with voltage meter?
Is the voltage less than 0.7
V?
Is the voltage more than
4.5 V?
Is the resistance less than
1 Ω?
EN(DOHC TURBO)-120
Check Yes
Go to step 9.
Go to step 4.
Repair poor con-
tact in ECM con-
nector.
Go to step 5.
Go to step 6.
Go to step 7.
No
Go to step 2.
Go to step 3.
Contact your
Subaru distributor.
NOTE:
Inspection by
DTM is required,
because probable
cause is deterio-
ration of multiple
parts.
Contact your
Subaru distributor.
NOTE:
Inspection by
DTM is required,
because probable
cause is deterio-
ration of multiple
parts.
Repair open cir-
cuit in harness
between ECM
and pressure sen-
sor connector.
Repair open cir-
cuit in harness
between ECM
and pressure sen-
sor connector.