Subaru Legacy (2005 year). Service manual — part 113

EN(H4SO 2.0)(diag)-41

ENGINE (DIAGNOSTICS)

Malfunction Indicator Light

15.Malfunction Indicator Light

A: PROCEDURE

1. Activation of malfunction indicator light. <Ref. to EN(H4SO 2.0)(diag)-42, ACTIVATION OF MALFUNCTION INDICATOR
LIGHT, Malfunction Indicator Light.>

↓

2. Check that the malfunction indicator light does not come on. <Ref. to EN(H4SO 2.0)(diag)-43, MALFUNCTION INDICATOR
LIGHT DOES NOT COME ON, Malfunction Indicator Light.>

↓

3. Check that the malfunction indicator light does not go off. <Ref. to EN(H4SO 2.0)(diag)-45, MALFUNCTION INDICATOR
LIGHT DOES NOT GO OFF., Malfunction Indicator Light.>

↓

4. Check that the malfunction indicator light does not blink. <Ref. to EN(H4SO 2.0)(diag)-46, MALFUNCTION INDICATOR LIGHT
DOES NOT BLINK., Malfunction Indicator Light.>

↓

5. Check that the malfunction indicator light remains blinking. <Ref. to EN(H4SO 2.0)(diag)-48, MALFUNCTION INDICATOR
LIGHT REMAINS BLINKING., Malfunction Indicator Light.>

EN(H4SO 2.0)(diag)-42

ENGINE (DIAGNOSTICS)

Malfunction Indicator Light

B: ACTIVATION OF MALFUNCTION

INDICATOR LIGHT

1) When the ignition switch is turned to ON (engine
OFF), the malfunction indicator light (A) in the com-
bination meter illuminates.

NOTE:
If the malfunction indicator light does not illuminate,
perform the diagnosis of malfunction indicator light
circuit or the combination meter circuit. <Ref. to
EN(H4SO 2.0)(diag)-43, MALFUNCTION INDICA-
TOR LIGHT DOES NOT COME ON, Malfunction
Indicator Light.>

2) After starting the engine, the malfunction indica-
tor light goes out. If it does not, either the engine or
emission control system is malfunctioning.

3) Turn the ignition switch to OFF and connect the
test mode connector.

(1) When the ignition switch is turned to ON
(engine OFF), the malfunction indicator light illu-
minates.
(2) After the engine starts, malfunction indicator
light blinks in a cycle of 0.5 Hz. (During diagno-
sis)

(3) Malfunction indicator light blinks at a cycle of
3 Hz after diagnosis if there is no trouble. Mal-
function indicator light illuminates if faulty.

(1) No faulty

(2) Trouble occurs

(3) ON

(4) OFF

(5) Ignition switch ON

(6) Engine start

EN-01984

(A)

EN-01679

(1)

(2)

(5)

(6)

(3)

(4)

(3)

(4)

(1) ON

(2) OFF

(3) Ignition switch ON

(4) 1 second

EN-01681

(2)

(1)

(4)

(3)

EN(H4SO 2.0)(diag)-43

ENGINE (DIAGNOSTICS)

Malfunction Indicator Light

C: MALFUNCTION INDICATOR LIGHT DOES NOT COME ON

DIAGNOSIS:
The malfunction indicator light circuit is open or shorted.
TROUBLE SYMPTOM:
When the ignition switch is turned to ON (engine OFF), malfunction indicator light does not come on.
WIRING DIAGRAM:

Step

Check

Yes

No

1

CHECK OUTPUT SIGNAL FROM ECM.
1) Turn the ignition switch to ON.
2) Measure the voltage between ECM con-
nector and chassis ground.

Connector & terminal

(B135) No. 15 (+) — Chassis ground (

−

):

Is the voltage less than 1 V?

Go to step 4.

Go to step 2.

2

CHECK POOR CONTACT.
Check for poor connection by shaking or pull-
ing ECM connector and harness.

Does the malfunction indicator
light illuminate?

Repair the poor
contact in ECM
connector.

Go to step 3.

EN-03469

BATTERY

3

B72

i3

B38

B135

IGNITION
SWITCH

COMBINATION
METER

i10

SBF-6

6

15

ECM

4

8

MAIN SBF

No.5

16

E

3

B72

1

3

4 5 6

2

B38

1 2 3 4

5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

i10

2

1

3 4

6 7 8 9 10

22

21

20

19

18

17

16

15

14

13

12

11

5

B135

8

1

28

20

5

6

7

2

9

4

3

10

24

22 23

25

11 12 13 14 15

26 27

16 17 18 19

21
29 30 31

32 33

34 35

EN(H4SO 2.0)(diag)-44

ENGINE (DIAGNOSTICS)

Malfunction Indicator Light

3

CHECK ECM CONNECTOR.
Check the connection of ECM connector.

Is the ECM connector correctly
connected?

Replace the ECM.
<Ref. to FU(H4SO
2.0)-34, Engine
Control Module
(ECM).>

Repair the con-
nection of ECM
connector.

4

CHECK HARNESS BETWEEN COMBINA-
TION METER AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Remove the combination meter. <Ref. to
IDI-15, Combination Meter.>
3) Disconnect the connector from ECM and
combination meter.
4) Measure the resistance of harness
between ECM and combination meter connec-
tor.

Connector & terminal

(B135) No. 15 — (i10) No. 16:

Is the resistance less than 1
Ω?

Go to step 5.

Repair the har-
ness and connec-
tor.

NOTE:
In this case, repair
the following item:
• Open circuit of
harness between
ECM and combi-
nation meter con-
nector
• Poor contact in
coupling connector

5

CHECK POOR CONTACT.
Check poor contact in combination meter con-
nector.

Is there poor contact in combi-
nation meter connector?

Repair the poor
contact in combi-
nation meter con-
nector.

Go to step 6.

6

CHECK HARNESS BETWEEN COMBINA-
TION METER AND IGNITION SWITCH CON-
NECTOR.
1) Turn the ignition switch to ON.
2) Measure the voltage between combination
meter connector and chassis ground.

Connector & terminal

(i10) No. 3 (+) — Chassis ground (

−

):

(i10) No. 4 (+) — Chassis ground (

−

):

Is the voltage more than 10 V? Replace the meter

case assembly of
combination
meter. <Ref. to IDI-
15, Combination
Meter.>

Check the follow-
ing and repair if
necessary.

NOTE:
• Blown out fuse
(No. 5)
• Open or short
circuit of harness
between fuse (No.
5) and battery ter-
minal
• Poor contact in
ignition switch con-
nector

Step

Check

Yes

No