Subaru Legacy 2003 Service Manual page 509

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
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 ( − − − − ):
Does the measured value exceed the spec-
ified value?
7 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. 15 — (E21) No. 2:
(B135) No. 1 — (E21) No. 1:
Is the measured value less than the speci-
fied value?
8 CHECK POOR CONTACT.
Check poor contact in pressure sensor con-
nector.
Is there poor contact in pressure sensor con-
nector?
9 CHECK HARNESS BETWEEN ECM AND
PRESSURE SENSOR CONNECTOR.
1) Turn ignition switch to OFF and Subaru
Select Monitor or the OBD-II general scan
tool switch to OFF.
2) Disconnect connector from pressure sen-
sor.
3) Turn ignition switch to ON and Subaru
Select Monitor or the OBD-II general scan
tool switch to ON.
4) Read data of intake manifold absolute pres-
sure signal using Subaru Select Monitor 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.
Step
EN(H4SO)-112
Value
4.5 V
1 Ω
There is poor contact.
119.5 kPa (896.5 mmHg,
35.29 inHg)
Yes
Go to step 7. Repair open circuit
in harness
between ECM and
pressure sensor
connector.
Go to step 8. Repair open circuit
in harness
between ECM and
pressure sensor
connector.
Repair poor con- Replace pressure
tact in pressure sensor. <Ref. to
sensor connector. FU(H4SO)-32,
Pressure Sensor.>
Repair battery Replace pressure
short circuit in har- sensor. <Ref. to
ness between FU(H4SO)-32,
ECM and pressure Pressure Sensor.>
sensor connector.
No