Subaru Legacy III (2000-2003 year). Manual - part 97

SC(H4SO)-22

STARTING/CHARGING SYSTEMS

BATTERY

MEMO:

ENGINE (DIAGNOSTICS)

EN(H4SO)

Page

1.

Basic Diagnostic Procedure ........................................................................2

2.

Check List for Interview...............................................................................4

3.

General Description ....................................................................................6

4.

Electrical Components Location................................................................10

5.

Engine Control Module (ECM) I/O Signal .................................................24

6.

Engine Condition Data ..............................................................................27

7.

Transmission Control Module (TCM) I/O Signal .......................................28

8.

Data Link Connector .................................................................................29

9.

OBD-II General Scan Tool ........................................................................30

10.

Subaru Select Monitor...............................................................................32

11.

Read Diagnostic Trouble Code .................................................................39

12.

Inspection Mode........................................................................................40

13.

Drive Cycle................................................................................................45

14.

Clear Memory Mode..................................................................................47

15.

Compulsory Valve Operation Check Mode ...............................................48

16.

Engine Malfunction Indicator Lamp (MI) ...................................................50

17.

Diagnostics for Engine Starting Failure.....................................................62

18.

List of Diagnostic Trouble Code (DTC) .....................................................83

19.

Diagnostic Procedure with Diagnostic Trouble Code (DTC) .....................90

20.

General Diagnostic Table........................................................................304

EN(H4SO)-2

ENGINE (DIAGNOSTICS)

BASIC DIAGNOSTIC PROCEDURE

1. Basic Diagnostic Procedure

A: PROCEDURE

1. ENGINE

Step

Value

Yes

No

1

CHECK ENGINE START FAILURE.
1) Ask the customer when and how the trou-

ble occurred using the interview check list. 
<Ref. to EN(H4SO)-4, CHECK, Check List 
for Interview.>

2) Start the engine.

Does the engine start?

Engine starts.

Go to step 2.

Inspection using 
“Diagnostics for 
Engine Start Fail-
ure”. <Ref. to 
EN(H4SO)-62, 
Diagnostics for 
Engine Starting 
Failure.>

2

CHECK ILLUMINATION OF CHECK ENGINE 
MALFUNCTION INDICATOR LAMP (MI).
Does CHECK ENGINE malfunction indicator 
lamp illuminate?

MI illuminates.

Go to step 3.

Inspection using 
“General Diagnos-
tics Table”. <Ref. 
to EN(H4SO)-304, 
INSPECTION, 
General Diagnos-
tic Table.>

3

CHECK INDICATION OF DTC ON DISPLAY.
1) Turn ignition switch to OFF.
2) Connect the Subaru Select Monitor or the 

OBD-II general scan tool to data link con-
nector.

3) Turn ignition switch to ON and the Subaru 

Select Monitor or OBD-II general scan tool 
switch to ON.

4) Read DTC on the Subaru Select Monitor or 

OBD-II general scan tool.
Does the Subaru Select Monitor or OBD-II 
general scan tool indicate DTC?

DTC indicated.

Go to step 4.

Repair the related 
parts.

NOTE:
If DTC is not
shown on display
although the MI il-
luminates, per-
form diagnostics of
MI (CHECK EN-
GINE malfunction
indicator lamp) cir-
cuit or combination
meter. <Ref. to
EN(H4SO)-50, En-
gine Malfunction
Indicator Lamp
(MI).>

4

PERFORM THE DIAGNOSIS.
1) Inspect using “Diagnostics Procedure with 

Diagnostic Trouble Code (DTC)”.

NOTE:

<Ref. to EN(H4SO)-90, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

NOTE:

Carry out the basic check, only when DTC
about automatic transmission is shown on dis-
play. <Ref. to EN(H4SO)-39, Read Diagnostic
Trouble Code.>

2) Repair the trouble cause.
3) Perform the clear memory mode. <Ref. to 

EN(H4SO)-47, Clear Memory Mode.>

4) Perform the inspection mode. <Ref. to 

EN(H4SO)-40, Inspection Mode.>
Does the Subaru Select Monitor or OBD-II 
general scan tool indicate DTC?

DTC indicated.

Inspect using 
“Diagnostics Pro-
cedure with Diag-
nostic Trouble 
Code (DTC)”.

NOTE:
<Ref. to
EN(H4SO)-90, Di-
agnostic Proce-
dure with
Diagnostic Trou-
ble Code (DTC).>

Complete the 
diagnosis.

EN(H4SO)-3

ENGINE (DIAGNOSTICS)

BASIC DIAGNOSTIC PROCEDURE

2. AUTOMATIC TRANSMISSION

When trouble code about automatic transmission is
shown on display, carry out the following basic
check. After that, carry out the replacement or re-
pair work.
1) ATF level check <Ref. to AT-30, Automatic
Transmission Fluid.>
2) Differential gear oil level check <Ref. to AT-31,
Differential Gear Oil.>
3) ATF leak check <Ref. to AT-30, Automatic
Transmission Fluid.>
4) Differential gear oil leak check <Ref. to AT-31,
Differential Gear Oil.>
5) Stall test <Ref. to AT-33, Stall Test.>
6) Line pressure test <Ref. to AT-36, Line Pressure
Test.>
7) Transfer clutch pressure test <Ref. to AT-38,
Transfer Clutch Pressure Test.>
8) Time lag test <Ref. to AT-35, Time Lag Test.>
9) Road test <Ref. to AT-32, Road Test.>
10) Shift characteristics <Ref. to AT-38, Transfer
Clutch Pressure Test.>