Basic Diagnostic Procedure - Subaru LEGACY 2003 Service Manual

ENGINE (DIAGNOSTICS)

1. Basic Diagnostic Procedure

A: PROCEDURE
1. WITH SUBARU SELECT MONITOR
1 CHECK ENGINE START FAILURE.
1) Ask the customer when and how the trou-
ble occurred using the interview check list.
<Ref. to EN(H4SOw/oOBD)-4, CHECK,
Check List for Interview.>
2) Start the engine.
Does the engine start?
2 CHECK ILLUMINATION OF CHECK ENGINE
MALFUNCTION INDICATOR LAMP (MIL).
<Ref. to EN(H4SOw/oOBD)-30, ACTIVATION
OF CHECK ENGINE MALFUNCTION INDICA-
TOR LAMP (MIL), Engine Malfunction Indica-
tor Lamp (MIL).>
Does MIL illuminate?
3 CHECK INDICATION OF DTC ON DISPLAY.
1) Turn ignition switch to OFF.
2) Connect the Subaru Select Monitor to data
link connector.
3) Turn ignition switch to ON and the Subaru
Select Monitor switch to ON.
4) Read DTC on the Subaru Select Monitor.
<Ref. to EN(H4SOw/oOBD)-24, WITH
SUBARU SELECT MONITOR, OPERA-
TION, Read Diagnostic Trouble Code
(DTC).>
Does the Subaru Select Monitor indicate
DTC? <Ref. to EN(H4SOw/oOBD)-57,
LIST, List of Diagnostic Trouble Code
(DTC).>
4 PERFORM THE DIAGNOSIS.
1) Perform the clear memory mode. <Ref. to
EN(H4SOw/oOBD)-28, OPERATION,
Clear Memory Mode.>
2) Perform the inspection mode. <Ref. to
EN(H4SOw/oOBD)-26, OPERATION,
Inspection Mode.>
Does the Subaru Select Monitor indicate
DTC? <Ref. to EN(H4SOw/oOBD)-57,
LIST, List of Diagnostic Trouble Code
(DTC).>
BASIC DIAGNOSTIC PROCEDURE
Step
EN(H4SOw/oOBD)-2
Value
Engine starts.
MIL illuminates.
DTC is displayed on Subaru
select monitor.
DTC is displayed on Subaru
select monitor.
Yes
Go to step 2. Inspection using
"Diagnostics for
Engine Starting
Failure". <Ref. to
EN(H4SOw/
oOBD)-39, Diag-
nostics for Engine
Starting Failure.>
Go to step 3. Inspection using
"General Diagnos-
tic Table". <Ref. to
EN(H4SOw/
oOBD)-102,
INSPECTION,
General Diagnos-
tic Table.>
Record diagnostic Repair the related
trouble code. parts.
Repair the trouble
NOTE:
cause. <Ref. to
If DTC
EN(H4SOw/
shown on display
oOBD)-59, Diag-
although the MIL il-
nostic Procedure
luminates,
with Diagnostic
form diagnostics of
Trouble Code
MIL (CHECK EN-
(DTC).> Go to
GINE malfunction
step 4.
indicator lamp) cir-
cuit or combination
meter.
EN(H4SOw/
oOBD)-30, Engine
Malfunction Indica-
tor Lamp (MIL).>
Record diagnostic Complete the
trouble code. diagnosis.
Repair the trouble
cause. <Ref. to
EN(H4SOw/
oOBD)-59, Diag-
nostic Procedure
with Diagnostic
Trouble Code
(DTC).> Go to
step 4.
No
is not
per-
<Ref. to