Subaru FORESTER 2001 Service Manual page 117

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 POOR CONTACT.
Check poor contact in ECM and pressure
sensor connector.
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. 9 (+) — Chassis ground (−):
5 CHECK INPUT SIGNAL FOR ECM.
Measure voltage between ECM and chassis
ground.
Connector & terminal
(B135) No. 8 (+) — Chassis ground (−):
6 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 (−):
Step
Is the value less than −7.2
kPa (−54 mmHg, −2.1
inHg)?
Is there poor contact in
ECM or pressure sensor
connector?
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?
EN(DOHC TURBO)-116
Check Yes
Go to step 3.
Repair poor con-
tact in ECM or
pressure sensor
connector.
Go to step 5.
Repair poor con-
tact in ECM con-
nector.
Go to step 6.
Go to step 7.
No
Go to step 2.
Even if MIL lights
up, the circuit has
returned to a nor-
mal condition at
this time.
Go to step 4.
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 intake mani-
fold pressure sen-
sor connector.