Mitsubishi Lancer Evolution IX. Manual - part 150

SYMPTOM PROCEDURES

SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR

54B-163

Step 2. Pulse check
Check the input signal from the headlamp switch.

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

Q: Is the check result normal?

All the signals are received normally. : 

Go to Step 

3.

The ignition switch (IG1) signal is not received. : 

Refer to inspection procedure L-2 "The 
ignition switch (IG1) signal is not received 

P.54B-242

."

The headlamp switch signal is not received. : 

Refer to inspection procedure L-4 "The 
column switch (lighting and turn-signal lamp 
switch) signal is not received 

P.54B-248

."

Step 3. Connector check: A-10X front-ECU 
connector

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Repair the defective connector.

Step 4. Voltage measurement at A-10X front-ECU 
connector

(1) Remove the front-ECU, and measure at the relay 

box side.

(2) Voltage between A-10X front-ECU connector 

terminal Nos.3, 4 and body earth

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Go to Step 5.

Step 5. Check the wiring harness between A-10X 
front-ECU connector terminal Nos.3, 4 and the 
battery.

• Check the power supply line 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.

System switch

Check condition

Ignition switch (IG1)

When turned from ACC 
to ON

Headlamp switch

When the lighting switch 
is turned to the 
HEADLAMP position

AC310572AB

Connector: A-10X

Relay box side

10

11

5

9 8 7 6

4 3

1

2

Battery

AC310572AB

Connector: A-10X

Relay box side

10

11

5

9 8 7 6

4 3

1

2

Battery

AC301541 DC

Connector A-10X
(Relay box side)

5

11

9

10

8 7 6

2

4 3

1

AC310572AB

Connector: A-10X

Relay box side

10

11

5

9 8 7 6

4 3

1

2

Battery

SYMPTOM PROCEDURES

SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR

54B-164

Step 6. Retest the system.
Check that the low-beam headlamps illuminate nor-
mally.

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 front-ECU.

INSPECTION PROCEDURE H-3: The high-beam headlamps do not illuminate normally.

CAUTION

Whenever the ECU is replaced, ensure that the 
input and output signal circuits are normal.

COMMENTS ON TROUBLE SYMPTOM

If the high-beam headlamps do not illuminate, the 
dimmer switch input circuit or the front-ECU may be 
defective.

POSSIBLE CAUSES

• Malfunction of the column switch

• Malfunction of the front-ECU

• Damaged harness wires and connectors

DIAGNOSTIC PROCEDURE

Step 1. Check that the headlamps operate.
Check that the low-beam headlamps illuminate and 
extinguish normally.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Refer to inspection procedure H-2 "The 
low-beam headlamps do not illuminate 
normally 

P.54B-162

."

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

BATTERY

FRONT-ECU

TAIL LAMP
RELAY: HI

RELAY
BOX

INPUT SIGNAL

· HEADLAMP AUTOMATIC
  SHUTDOWN
· TAIL LAMP SWITCH

· COMBINATION METER
· HEADLAMP (LH)

HEADLAMP (RH)

Headlamp Relay (High-Beam) Circuit

SYMPTOM PROCEDURES

SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR

54B-165

Step 2. Pulse check
Check the input signal from the dimmer switch.

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

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Refer to inspection procedure L-4 "The 
column switch (lighting and turn-signal lamp 
switch) signal is not received 

P.54B-248

."

Step 3. Retest the system.
Check that the high-beam headlamps illuminate nor-
mally.

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 front-ECU.

INSPECTION PROCEDURE H-4: The high-beam and low-beam headlamps do not illuminate when the 
passing switch is operated.

CAUTION

Whenever the ECU is replaced, ensure that the 
input and output signal circuits are normal.

COMMENTS ON TROUBLE SYMPTOM

If the low-beam and high-beam headlamps are nor-
mal, the passing switch input signal circuit or the 
front-ECU may be defective.

POSSIBLE CAUSES

• Malfunction of the column switch

• Malfunction of the front-ECU

• Damaged harness wires and connectors

DIAGNOSTIC PROCEDURE

Step 1. Check that the headlamps operate.
Check that the low-beam and high-beam headlamps 
work normally.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the headlamps. Refer to trouble 
symptom chart 

P.54B-33

.

Step 2. Pulse check
Check the input signal from the passing switch.

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

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Refer to inspection procedure L-4 "The 
column switch (lighting and turn-signal lamp 
switch) signal is not received 

P.54B-248

."

Step 3. Retest the system.
When the passing switch is turned on, check if the 
headlamps illuminate normally.

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 front-ECU.

System switch

Check condition

Dimmer switch

When the dimmer switch 
is turned from off to on

System switch

Check condition

Passing lamp switch

When the passing switch 
is turned from off to on

SYMPTOM PROCEDURES

SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR

54B-166

INSPECTION PROCEDURE H-5: The headlamp automatic shutdown function does not work normally.

CAUTION

Whenever the ECU is replaced, ensure that the 
input and output signal circuits are normal.

COMMENTS ON TROUBLE SYMPTOM

The ETACS-ECU operates this function in accord-
ance with the input signals below.

• Ignition switch (IG1)

• Driver's door switch

• Tail lamp switch

• Headlamp switch

If this function does not work normally, these input 
signal circuit(s), the front-ECU or the ETACS-ECU 
may be defective. Note that this function can be disa-
bled/enabled by the adjustment function (default set-
ting; enabled).

POSSIBLE CAUSES

• Malfunction of the driver's door switch

• Malfunction of the front-ECU

• Malfunction of the column switch

• Malfunction of the ETACS-ECU

• Damaged harness wires and connectors

DIAGNOSTIC PROCEDURE

Step 1. Check the adjustment function.
Check that the headlamp automatic shutdown func-
tion has been enabled by using the adjustment func-
tion.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Enable the headlamp automatic shutdown 
function by using the adjustment function. 
Refer to 

P.54B-302

.

Step 2. Check that the headlamps operate.
Check that the low-beam and high-beam headlamps 
work normally.

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Repair the headlamps. Refer to trouble 
symptom chart 

P.54B-33

.

ETACS-ECU

INPUT SIGNAL

· DRIVER'S DOOR SWITCH

· TAIL LAMP SWITCH

· IGNITION SWITCH (IG1)

· HEADLAMP SWITCH

Headlamp Automatic Shutdown Function