Subaru Legacy 2004 Service Manual page 1360

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
6 CHECK HARNESS BETWEEN ECM AND
MASS AIR FLOW SENSOR CONNECTOR.
Measure the resistance of harness between
ECM and chassis ground.
Connector & terminal
(B136) No. 23 — Chassis ground:
(B136) No. 31 — Chassis ground:
(B136) No. 35 — Chassis ground:
7 CHECK POOR CONTACT.
Check poor contact in mass air flow sensor
connector.
Check
Is the resistance more than 1
M'?
Is there poor contact in mass
air flow sensor connector?
EN(H4DOTC)(diag)-71
ENGINE (DIAGNOSTICS)
Yes
Go to step 7. Repair the ground
short circuit
between ECM and
mass air flow sen-
sor connector.
Repair the poor Replace the mass
contact in mass air air flow and intake
flow sensor con- air temperature
nector. sensor. <Ref. to
FU(H4DOTC)-28,
Mass Air Flow and
Intake Air Temper-
ature Sensor.>
No