Subaru FORESTER 2001 Service Manual page 110

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
No.
1 CONNECT SUBARU SELECT MONITOR OR
THE OBD-II GENERAL SCAN TOOL, AND
READ DATA.
1) Turn ignition switch to OFF.
2) Connect Subaru Select Monitor or the
OBD-II general scan tool to data link connec-
tor.
3) Turn ignition switch to ON and Subaru
Select Monitor or the OBD-II general scan
tool switch to ON.
4) Start engine.
5) Read data of mass air flow sensor signal
using Subaru Select Monitor or OBD-II gen-
eral scan tool.
NOTE:
¼ Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE".
<Ref. to EN(DOHC TURBO)-36, Subaru
Select Monitor.>
¼ 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 ignition switch to OFF and Subaru
Select Monitor or the OBD-II general scan
tool switch to OFF.
2) Disconnect connector from mass air flow
sensor.
3) Turn ignition switch to ON and Subaru
Select Monitor or the OBD-II general scan
tool switch to ON.
4) Read data of mass air flow sensor signal
using Subaru select monitor or OBD-II gen-
eral scan tool.
NOTE:
¼ Subaru Select Monitor
For detailed operation procedure, refer to the
"READ CURRENT DATA FOR ENGINE".
<Ref. to EN(DOHC TURBO)-36, Subaru
Select Monitor.>
¼ OBD-II general scan tool
For detailed operation procedures, refer to the
OBD-II General Scan Tool Instruction Manual.
Step
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(DOHC TURBO)-109
Check Yes
Even if MIL lights
up, the circuit has
returned to a nor-
mal condition at
this time.
Repair battery
short circuit in
harness between
mass air flow sen-
sor and ECM con-
nector. After
repair, replace
ECM.
Engine (Diagnostics)
No
Go to step 2.
Replace mass air
flow sensor.