Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 211

EN(H4DOTC)(diag)-68

Malfunction Indicator Light

ENGINE (DIAGNOSTICS)

3) If the diagnostic system detects a misfire which

could damage the catalyst, the malfunction indica-

tor light will blink at a cycle of 1 Hz.

4) Turn the ignition switch to OFF and connect the

delivery (test) mode connector (A) located under

the glove box.

(1) When the ignition switch is turned to ON

(engine OFF), the malfunction indicator light il-

luminates.

(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) ON
(2) OFF
(3) Ignition switch ON
(4) Engine start
(5) Misfire start
(6) 1 second

(2)

(1)

(3)

(4)

(5)

(6)

EN-01680

EN-06146

(A)

(1) ON
(2) OFF
(3) Ignition switch ON
(4) 1 second

EN-01681

(2)

(1)

(4)

(3)

EN(H4DOTC)(diag)-69

Malfunction Indicator Light

ENGINE (DIAGNOSTICS)

C: MALFUNCTION INDICATOR LIGHT DOES NOT COME ON

TROUBLE SYMPTOM:

When the ignition switch is turned to ON (engine OFF), malfunction indicator light does not illuminate.

D: MALFUNCTION INDICATOR LIGHT DOES NOT GO OFF

TROUBLE SYMPTOM:

Although malfunction indicator light comes on when the engine runs, DTC is not shown on the Subaru Select

Monitor or general scan tool display.

Step

Check

Yes

No

1

CHECK DTC.

Is DTC of LAN system dis-
played? <Ref. to LAN(diag)-28,
OPERATION, Read Diagnostic
Trouble Code (DTC).>

Check the appro-
priate DTC using
the “List of Diag-
nostic Trouble
Code (DTC)”.
<Ref. to
LAN(diag)-32, List
of Diagnostic Trou-
ble Code (DTC).>

Replace the meter
case assembly of
combination
meter. <Ref. to IDI-
16, Combination
Meter.>

Step

Check

Yes

No

1

CHECK DTC.

Is DTC of engine or LAN sys-
tem displayed? <Ref. to
EN(H4DOTC)(diag)-48,
OPERATION, Read Diagnostic
Trouble Code (DTC).>

Check the appropri-
ate DTC using the
“List of Diagnostic
Trouble Code
(DTC)”. <Ref. to
EN(H4DOTC)(diag)
-87, List of Diagnos-
tic Trouble Code
(DTC).> <Ref. to
LAN(diag)-32, List
of Diagnostic Trou-
ble Code (DTC).>

Go to step

2.

2

CHECK COMBINATION METER.
Perform the self-diagnosis for combination
meter system. <Ref. to IDI-5, SELF-DIAGNO-
SIS, INSPECTION, Combination Meter Sys-
tem.>

Does the malfunction indicator
light illuminate and go off nor-
mally?

Replace the ECM.
<Ref. to FU(STI)-
59, Engine Control
Module (ECM).>
<Ref. to FU(w/o
STI)-57, Engine
Control Module
(ECM).>

Replace the meter
case assembly of
combination
meter. <Ref. to IDI-
16, Combination
Meter.>

EN(H4DOTC)(diag)-70

Malfunction Indicator Light

ENGINE (DIAGNOSTICS)

E: MALFUNCTION INDICATOR LIGHT DOES NOT BLINK

DIAGNOSIS:

• The malfunction indicator light circuit is open or shorted.

• The delivery (test) mode connector circuit is open.

TROUBLE SYMPTOM:

Malfunction indicator light does not blink during Inspection Mode.

WIRING DIAGRAM:

• Engine electrical system, without SI-DRIVE <Ref. to WI-32, WITHOUT SI-DRIVE, WIRING DIAGRAM,

Engine Electrical System.>

• Engine electrical system, with SI-DRIVE <Ref. to WI-48, WITH SI-DRIVE, WIRING DIAGRAM, Engine

Electrical System.>

ECM

1

1

1

B76

B75

B364

B363

1
2

B364

B76

B75

1
2

B363

B122

3 4

5 6

1 2

7 8

2 3 4 5

1

6 7 8

i97

i10

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 36 37 38 39 40

21

*

**

22

i97

*

4

34

i10

2

B72

1

3

4 5 6

2

16

10 11 12 13 14 15

25

24

30

9

8

7

17 18 19 20
28

21 22 23

29

32

31

1

2

3

4

5

6

27

26

33 34 35

B136

B136

*

B122

1

B72

3

*

EN-09248

E

SBF-6

E

MAIN SBF

No. 5

IGNITION

SWITCH

BATTERY

DRIVE CIRCUIT

COMBINATION

METER

: TERMINAL No. OPTIONAL ARRANGEMENT

DELIVERY

(TEST)

MODE

CONNECTOR

TEST MODE

SUB

CONNECTOR

EN(H4DOTC)(diag)-71

Malfunction Indicator Light

ENGINE (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK STATUS OF MALFUNCTION INDI-
CATOR LIGHT.
1) Turn the ignition switch to OFF.
2) Check the delivery (test) mode connector is
disconnected.
3) Turn the ignition switch to ON. (engine OFF)

Does the malfunction indicator
light illuminate?

Go to step

2.

Repair the malfunc-
tion indicator light
circuit. <Ref. to
EN(H4DOTC)(diag)
-69, MALFUNC-
TION INDICATOR
LIGHT DOES NOT
COME ON, Mal-
function Indicator
Light.>

2

CHECK HARNESS BETWEEN ECM AND DE-
LIVERY (TEST) MODE CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Connect the delivery (test) mode connector.
4) Measure the resistance of harness between
ECM connectors.

Connector & terminal

(B136) No. 34 — (B136) No. 4:

Is the resistance less than 1 Ω? Go to step

3.

Repair the harness
and connector.
NOTE:

In this case, repair
the following item:
• Open circuit in
harness between
ECM connector
• Poor contact of
each

connector

between ECM con-
nector

3

CHECK FOR POOR CONTACT.
Check for poor contact of ECM connector.

Is there poor contact of ECM
connector?

Repair the poor
contact of ECM
connector.

Replace the ECM.
<Ref. to FU(STI)-
59, Engine Control
Module (ECM).>
<Ref. to FU(w/o
STI)-57, Engine
Control Module
(ECM).>