Subaru 2002 IMPREZA Service Manual page 1261

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Step
1 CONNECT SUBARU SELECT MONITOR OR
THE OBD-II GENERAL SCAN TOOL, AND
READ DATA.
1)Turn the ignition switch to OFF.
2)Connect the Subaru Select Monitor or OBD-
II general scan tool to data link connector.
3)Turn the ignition switch to ON and Subaru
Select Monitor or OBD-II general scan tool
switch to ON.
4)Start the engine.
5)Read the data of mass air flow sensor signal
using Subaru Select Monitor or OBD-II general
scan tool.
NOTE:
•Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE".
<Ref. to EN(TURBO)-34, Subaru Select Moni-
tor.>
•OBD-II general scan tool
For detailed operation procedures, refer to the
OBD-II General Scan Tool Instruction Manual.
2 CHECK HARNESS BETWEEN ECM AND
MASS AIR FLOW SENSOR CONNECTOR.
1)Turn the ignition switch to OFF and Subaru
Select Monitor or the OBD-II general scan tool
switch to OFF.
2)Disconnect the connector from mass air flow
sensor.
3)Turn the ignition switch to ON and Subaru
Select Monitor or the OBD-II general scan tool
switch to ON.
4)Read the data of mass air flow sensor signal
using Subaru Select Monitor or OBD-II general
scan tool.
NOTE:
•Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE".
<Ref. to EN(TURBO)-34, Subaru Select Moni-
tor.>
•OBD-II general scan tool
For detailed operation procedures, refer to the
OBD-II General Scan Tool Instruction Manual.
Check
Is the value equal to or more
than 1.3 g/sec (0.172 lb/min) or
0.3 V and equal to or less than
240 g/sec (32 lb/min) or 4.58
V?
Is the value more than 240
g/sec (32 lb/min) or 4.58 V in
function mode F06?
EN(TURBO)-101
ENGINE (DIAGNOSTICS)
Yes
Even if MIL lights Go to step 2.
up, the circuit has
returned to a nor-
mal condition at
this time.
Repair the battery Replace the mass
short circuit in har- air flow sensor.
ness between
mass air flow sen-
sor and ECM con-
nector. After
repair, replace the
ECM.
No