Subaru Legacy III (2000-2003 year). Manual - part 155

EN(H4SO)-232

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

BA:DTC P0519 — IDLE AIR CONTROL CIRCUIT SYSTEM PERFORMANCE —

• DTC DETECTING CONDITION:

• Immediately at fault recognition

• TROUBLE SYMPTOM:

• Engine keeps running at higher revolution than specified idling revolution.

CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode<Ref. to EN(H4SO)-47, OPER-
ATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4SO)-40, OPERATION, Inspection 
Mode.> .
• WIRING DIAGRAM:

EN-01134

F44

B61

6

RHD

RHD

20

6

5

19

B21

E2

ECM

2

5

6

3

4

1

3

4

1

2

IDLE 

AIR CONTROL

SOLENOID 

VALVE

E7

B22

E3

B47

B134

B47

3

4

1

2

5

6

B134

1 2

3 4

5 6

7 8

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

24 25

26 27 28 29

30 31 32 33

34 35

B22

1 2 3 4
5 6 7 8
9 10 11 12

13 14 15 16

E7

1

3

4 5 6

2

B21

1 2

3 4

5

6 7

8

9 10

11 12

13

14 15

16

17 18

19 20

SBF-5

BATTERY

MAIN RELAY

1

2

3

5

4

6

1

1 2 3 4
5 6 7 8

F44

LHD

LHD

EN(H4SO)-233

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK ANY OTHER DTC ON DISPLAY.
Is any other DTC displayed?

DTC indicated.

Inspect the rele-
vant DTC using 
“List of Diagnostic 
Trouble Code 
(DTC)”. <Ref. to 
EN(H4SO)-83, List 
of Diagnostic 
Trouble Code 
(DTC).>  

NOTE:
In this case, it is
not necessary to
inspect DTC
P0519.

Go to step 2.

2

CHECK AIR INTAKE SYSTEM.
1) Turn ignition switch to ON.
2) Start engine, and idle it.
3) Check the following items.
•Loose installation of intake manifold, idle air 
control solenoid valve and throttle body
•Cracks of intake manifold gasket, idle air con-
trol solenoid valve gasket and throttle body 
gasket
•Disconnections of vacuum hoses

Is there a fault in air intake system?

There is a fault.

Repair air suction 
and leaks.

Go to step 3.

3

CHECK THROTTLE CABLE.
Does throttle cable have play for adjustment?

Throttle cable has play for 
adjustment.

Go to step 4.

Adjust throttle 
cable. <Ref. to 
SP(H4SO)-10, 
Accelerator Con-
trol Cable.>

4

CHECK AIR BY-PASS LINE.
1) Turn ignition switch to OFF.
2) Remove idle air control solenoid valve from 

throttle body. <Ref. to FU(H4SO)-34, 
REMOVAL, Idle Air Control Solenoid 
Valve.>

3) Confirm that there are no foreign particles 

in by-pass air line.
Are foreign particles in by-pass air line?

Foreign particles are in by-
pass air line.

Remove foreign 
particles from by-
pass air line.

Replace idle air 
control solenoid 
valve. <Ref. to 
FU(H4SO)-34, Idle 
Air Control Sole-
noid Valve.>

EN(H4SO)-234

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

BB:DTC P0565 — CRUISE CONTROL ON SIGNAL —

• DTC DETECTING CONDITION:

• Two consecutive driving cycles with fault

CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode<Ref. to EN(H4SO)-47, OPER-
ATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4SO)-40, OPERATION, Inspection 
Mode.> .
• WIRING DIAGRAM:

EN-01135

CCM

3

22

B94

TCM

B55

B94

1 2 3 4 5 6 7 8 9 10

11 12 13 14 15 16 17 18 19 20

B55

1 2 3 4

10 11 12
19 20 21

13

5 6

14 15

7

8

9

16

17

18

22

23

24

EN(H4SO)-235

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK HARNESS BETWEEN TCM AND 
CCM CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connectors from TCM and 

CCM.

3) Measure resistance of harness between 

TCM and CCM connector.

Connector & terminal

(B55) No. 22 - (B94) No. 3:

Is the measured value less than the speci-
fied value?

1 

Ω

Go to step 2.

Repair open circuit 
in harness 
between TCM and 
CCM connector.

2

CHECK HARNESS BETWEEN TCM AND 
CCM CONNECTOR.
Measure resistance of harness between TCM 
and chassis ground.

Connector & terminal

(B55) No. 22 - Chassis ground:

Does the measured value exceed the specified 
value?

1 M

Ω

Go to step 3.

Repair short circuit 
in harness 
between TCM and 
CCM connector.

3

CHECK INPUT SIGNAL FOR TCM.
1) Connect connector to TCM and CCM.
2) Lift-up the vehicle or set the vehicle on free 

rollers.

CAUTION:

On AWD models, raise all wheels off 
ground.

3) Start the engine.
4) Cruise control main switch to ON.
5) Move selector lever to “D” and slowly 

increase vehicle speed to 50 km/h (31 
MPH).

6) Cruise control command switch to ON.
7) Measure voltage between TCM and chas-

sis ground.

Connector & terminal

(B55) No. 22 - Chassis ground:

Is the measured value less than the speci-
fied value?

1 V

Go to step 4.

Check cruise con-
trol command 
switch circuit. 
<Ref. to CC-8, 
INSPECTION, 
Cruise Control 
Command 
Switch.>

4

CHECK POOR CONTACT.
Check poor contact in TCM connector. 
Is there poor contact in TCM connector?

There is poor contact.

Repair poor con-
tact in TCM con-
nector.

Replace TCM.  
<Ref. to AT-76, 
Transmission Con-
trol Module 
(TCM).>