Mitsubishi Lancer Evolution IX. Manual - part 255

INPUT SIGNAL PROCEDURES

SMART WIRING SYSTEM (SWS) USING SWS MONITOR

54C-279

Step 4. Check the wiring harness between C-20 
fog lamp switch connector terminal No.6 and 
body earth.

NOTE: 

Prior to the wiring harness inspection, check joint 
connector C-101 <LH driver vehicles> or C-06 <RH 
drive vehicles>, and repair if necessary.

• Check the earth wires for open circuit.

Q: Is the check result normal?

YES : 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00 

− How to 

Cope with Intermittent Malfunction 

P.00-5

).

NO : 

Repair the wiring harness.

Step 5. Connector check: C-227 ETACS-ECU 
connector

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Repair the defective connector.

AC310446

Harness side

AH

Connector: C-20
<LHD>

AC310456

Harness side

AI

Connector: C-20
<RHD>

AC310446

Connector: C-101
<LHD>

AF

Harness side

AC310456

Connector: C-06
<RHD>

AG

Harness side

AC310450

Connector: C-227

AG

Junction block 
(rear view)

Harness side

<LHD>

28

37

43

29

44

38

23

32

41

24

25

26

27

34

42

36 35

33

21

22

30

39

40

31

AC310461

Harness side

Junction block (rear view)

Connector: C-227

AF

<RHD>

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

INPUT SIGNAL PROCEDURES

SMART WIRING SYSTEM (SWS) USING SWS MONITOR

54C-280

Step 6. Check the wiring harness between C-227 
ETACS-ECU connector terminal No.21 and C-20 
fog lamp switch connector terminal No.5.

• Check the input line for open circuit.

Q: Is the check result normal?

YES : 

Go to Step 7.

NO : 

Repair the wiring harness.

Step 7. Pulse check.
Check the input signal from the rear fog lamp switch.

OK: The M.U.T.-II/III sounds or the voltmeter 
needle fluctuates.

Q: Is the check result normal?

YES : 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00 

− How to 

Cope with Intermittent Malfunction 

P.00-5

).

NO : 

Replace the ETACS-ECU.

AC310446

Harness side

AH

Connector: C-20
<LHD>

AC310456

Harness side

AI

Connector: C-20
<RHD>

AC310450

Connector: C-227

AG

Junction block 
(rear view)

Harness side

<LHD>

28

37

43

29

44

38

23

32

41

24

25

26

27

34

42

36 35

33

21

22

30

39

40

31

AC310461

Harness side

Junction block (rear view)

Connector: C-227

AF

<RHD>

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

System switch

Check condition

Rear fog lamp switch

When the switch is 
turned from off to on

INPUT SIGNAL PROCEDURES

SMART WIRING SYSTEM (SWS) USING SWS MONITOR

54C-281

INSPECTION PROCEDURE L-9: The key reminder switch signal is not received.

CAUTION

Whenever the ECU is replaced, ensure that the 
input signal circuit is normal.

COMMENTS ON TROUBLE SYMPTOM

Input signal from the key reminder switch is used to 
operate the functions below. If the signal is abnormal, 
these functions will not work normally.

• Key reminder function

• Keyless entry system

• Room lamps

POSSIBLE CAUSES

• Malfunction of the key reminder switch

• Malfunction of the ETACS-ECU

• Damaged harness wires and connectors

ETACS-
ECU

KEY 
REMINDER 
SWITCH

Wire colour code
B : Black     LG : Light green     G : Green     L : Blue     W : White     Y : Yellow     SB : Sky blue
BR : Brown     O : Orange     GR : Gray     R : Red     P : Pink     V : Violet   

WHEN KEY
IS REMOVED

Key Reminder Switch Input Circuit

INPUT SIGNAL PROCEDURES

SMART WIRING SYSTEM (SWS) USING SWS MONITOR

54C-282

DIAGNOSIS PROCEDURE

Step 1. Connector check: C-207 key reminder 
switch connector

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the defective connector.

Step 2. Check the key reminder switch.
Refer to GROUP 54A 

− Ignition switch 

P.54A-30

.

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Replace the key reminder switch.

Step 3. Resistance measurement at the C-207 key 
reminder switch connector

(1) Disconnect the connector, and measure at the 

wiring harness side.

(2) Resistance between C-207 key reminder switch 

connector terminal No.4 and body earth

OK: 2 

Ω or less

Q: Is the check result normal?

YES : 

Go to Step 5.

NO : 

Go to Step 4.

AC310479

AC

Connector: C-207
<LHD>

Harness side

2
7 6

1
3

5 4

AC310481AC

Harness side

Connector: C-207
<RHD>

AC310479

AC

Connector: C-207
<LHD>

Harness side

2
7 6

1
3

5 4

AC310481AC

Harness side

Connector: C-207
<RHD>

AC301541

2
7 6

1
3

5 4

GY

Connector C-207
(Harness side)