Subaru Impreza 2003 Service Manual page 1294

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
Step
5 CHECK HARNESS BETWEEN MASS AIR
FLOW AND INTAKE AIR TEMPERATURE
SENSOR AND ECM CONNECTOR.
1)Turn the ignition switch to OFF.
2)Measure the resistance of harness between
mass air flow and intake air temperature sen-
sor and engine ground.
Connector & terminal
(B3) No. 5 — Engine ground:
Check
Is the resistance less than 5
Ω?
EN(H4DOTC)-118
Yes
Replace the mass Repair the har-
air flow and intake ness and connec-
air temperature tor.
sensor. <Ref. to
NOTE:
FU(H4DOTC)-34,
In this case, repair
Mass Air Flow and
the following:
Intake Air Temper-
• Open circuit in
ature Sensor.>
harness between
mass air flow and
intake air tempera-
ture sensor and
ECM connector
• Poor contact in
mass air flow and
intake air tempera-
ture sensor
• Poor contact in
ECM
• Poor contact in
joint connector
No