Subaru Legacy 2002 Service Manual page 637

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (Diagnostics)
No.
4 CHECK HARNESS BETWEEN INTAKE AIR
TEMPERATURE AND PRESSURE SENSOR
AND ECM CONNECTOR.
Measure voltage between intake air tempera-
ture and pressure sensor connector and
engine ground.
Connector & terminal
(E20) No. 2 (+) — Engine ground (−):
5 CHECK HARNESS BETWEEN INTAKE AIR
TEMPERATURE AND PRESSURE SENSOR
AND ECM CONNECTOR.
1) Turn ignition switch to OFF.
2) Measure resistance of harness between
intake air temperature and pressure sensor
connector and engine ground.
Connector & terminal
(E20) No. 1 — Engine ground:
Step
Is the voltage more than 3
V?
Is the resistance less than
5 Ω?
EN-120
Check Yes
Go to step 5.
Replace intake air
temperature and
pressure sensor.
<Ref. to FU-37,
Intake Air Tem-
perature and
Pressure Sensor.>
No
Repair harness
and connector.
NOTE:
In this case,
repair the follow-
ing:
¼ Open circuit in
harness between
intake air tem-
perature and
pressure sensor
and ECM connec-
tor
¼ Poor contact in
intake air tem-
perature and
pressure sensor
¼ Poor contact in
ECM
¼ Poor contact in
coupling connec-
tor (B21)
¼ Poor contact in
joint connector
(B83)
Repair harness
and connector.
NOTE:
In this case,
repair the follow-
ing:
¼ Open circuit in
harness between
intake air tem-
perature and
pressure sensor
and ECM connec-
tor
¼ Poor contact in
intake air tem-
perature and
pressure sensor
¼ Poor contact in
ECM
¼ Poor contact in
coupling connec-
tor (B21)
¼ Poor contact in
joint connector
(B83)