Mitsubishi Lancer (4A9 engine). Manual — part 114

HEADLAMP

CHASSIS ELECTRICAL

54A-118

Inspection Procedure 8: The auto lamp function does not work normally.

CAUTION

Whenever the ECU is replaced, ensure that the
power supply circuit, the earth circuit and the
communication circuit are normal.
OPERATION
The ETACS-ECU operates this function in accord-
ance with the input signals from driving distance,
lighting control sensor, and column switch (auto lamp
switch). Also, when the column switch (lighting
switch) is in the "AUTO" position, and when an
abnormality is present to the auto lamp circuit, the
fail-safe function is activated and the low beam is
turned ON at all times regardless of the brightness
around the vehicle.

COMMENTS ON TROUBLE SYMPTOM
If the auto lamp function does not work normally, the
above input signal circuit(s) or the ETACS-ECU may
have a problem.

PROBABLE CAUSES

• Malfunction of the lighting control sensor

• Malfunction of the column switch

• Malfunction of the ETACS-ECU

• Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES :

Go to Step 2.

NO :

Repair the CAN bus line (Refer to GROUP
54C

− Troubleshooting ).

STEP 2. M.U.T.-III diagnosis code
Check if diagnosis code is set to the LIN.

Q: Is the diagnosis code set?

YES :

Refer to diagnosis code chart .

NO :

Go to Step 3.

STEP 3. M.U.T.-III other system diagnosis code
Check if diagnosis code is set to the ETACS-ECU.

Q: Is the diagnosis code set?

YES :

Troubleshoot the ETACS-ECU (Refer to ).

NO :

Go to Step 4.

STEP 4. Check that the headlamps operate.
Check that the headlamps (low-beam) illuminate nor-
mally.

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Refer to Inspection Procedure 1 "None of
the low-beam headlamps illuminate." .

STEP 5. M.U.T.-III data list
Use the ETACS-ECU service data to check the sig-
nals related to the operation of auto lamp function.

• Turn the lighting switch to the "AUTO" position.

OK: Normal condition is displayed.

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Troubleshoot the ETACS-ECU. Refer to
Inspection Procedure 11 "The column
switch signal is not received" .

STEP 6. Lighting control sensor check
Check the lighting control sensor. Refer to .

Q: Is the check result normal?

YES :

Go to Step 7.

NO :

Replace the lighting control sensor.

STEP 7. Retest the system
Check that the auto lamp function works normally.

Q: Is the check result normal?

YES :

The trouble can be an intermittent

malfunction (Refer to GROUP 00

− How to

use Troubleshooting/inspection Service
Points

− How to Cope with Intermittent

Malfunction ).

NO :

Replace the ETACS-ECU.

Item No.

Item name

Normal
condition

Item 348

Headlamp
switch (auto)

ON

HEADLAMP

CHASSIS ELECTRICAL

54A-119

Inspection Procedure 9: One of the position lamps, the licence plate lamps or the tail lamps does not
illuminate.

COMMENTS ON TROUBLE SYMPTOM
If one of the position lamps, the licence plate lamps
or tail lamps does not illuminate normally, the har-
ness, connector(s), or bulb(s) may have a problem,
or the fuse may be burned out.

PROBABLE CAUSES

• Malfunction of bulbs

• Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Connector check: A-35 (position lamp
LH) or A-53 (position lamp RH) headlamp
assembly connector, F-23 (LH) or F-08 (RH) rear
combination lamp connector, F-22 (LH) or F-09
(RH) tail lamp <LANCER> connector and F-15
(LH) or F-13 (RH) licence plate lamp connector

Q: Is the check result normal?

YES :

Go to Step 2.

NO :

Repair the defective connector.

STEP 2. Bulb check
Check the bulb(s) of the lamp that does not illumi-
nate.

Q: Is the check result normal?

YES <LANCER> :

Go to Step 3.

YES <LANCER SPORTBACK> :

Go to Step 8.

NO :

Replace the bulb(s) of the lamp that does
not illuminate.

ACA00916

A-53 (B)

Connectors: A-35, A-53

AJ

A-35 (B)

ACA00886

BC

Connectors: C-304, C-311 <LHD>

ETACS-ECU

C-304

C-311

ACA00887

BD

Connectors: C-304, C-311 <RHD>

ETACS-ECU

C-304

C-311

ACA00901AC

F-08

F-23

F-09 (GR)

F-22 (GR)

F-15 (GR)

F-13 (GR)

Connectors: F-08, F-09, F-13, F-15, F-22,
F-23 <LANCER>

AC801775BS

F-08

F-13

F-15

F-23

Connectors: F-08, F-13, F-15, F-23
<LANCER SPORTBACK>

HEADLAMP

CHASSIS ELECTRICAL

54A-120

STEP 3. Resistance measurement at the A-35
(position lamp LH) or A-53 (position lamp RH)
headlamp assembly connector, F-23 (LH) or F-08
(RH) rear combination lamp connector, F-22 (LH)
or F-09 (RH) tail lamp <LANCER> connector and
F-15 (LH) or F-13 (RH) licence plate lamp
connector
(1) Disconnect the connector, and measure at the

wiring harness side.

(2) Measure the resistance between the connector of

lamp which does not illuminate and the body
earth.

• Measure the resistance between the A-35

(LH), A-53 (RH) headlamp assembly connec-
tor terminal No. 6 and the body earth. <Posi-
tion lamp>

• Measure the resistance between the F-23

(LH) and F-08 (RH) rear combination lamp
connector terminal No. 1 and the body earth.

• Measure the resistance between the F-22

(LH), F-09 (RH) tail lamp <LANCER> connec-
tor terminal No. 1 and the body earth.

• Measure the resistance between the F-15

(LH), F-13 (RH) licence plate lamp connector
terminal No. 1 and the body earth.

OK: Continuity exists (2

Ω or less)

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Go to Step 4.

STEP 4. Wiring harness check between the A-35
(position lamp LH) or A-53 (position lamp RH)
headlamp assembly connector terminal No. 6, F-
23 (LH) or F-08 (RH) rear combination lamp
connector terminal No. 1, F-22 (LH) or F-09 (RH)
tail lamp <LANCER> connector terminal No. 1 or
F-15 (LH) or F-13 (RH) licence plate lamp
connector terminal No. 1 and the body earth
NOTE: Before the wiring harness check, check the
intermittent connector F-28 or F-19, and repair that if
necessary.

• Check the earth wires for open circuit.

Q: Is the check result normal?

YES :

Go to Step 7.

NO :

Repair the wiring harness.

STEP 5. Connector check: C-304 (position lamp),
C-311 (tail lamp or licence plate lamp) ETACS-
ECU connector

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Repair the defective connector.

STEP 6. Wiring harness check between the A-35
(position lamp LH) or A-53 (position lamp RH)
headlamp assembly connector terminal No. 4
and C-304 ETACS-ECU connector terminal No. 3
(LH) or terminal No. 7 (RH) and between F-23 (LH)
or F-08 (RH) rear combination lamp connector
terminal No. 3, F-22 (LH) or F-09 (RH) tail lamp
<LANCER> connector terminal No. 2 or F-15 (LH)
or F-13 (RH) licence lamp connector terminal No.
2 and C-311 ETACS-ECU connector terminal No.
10 (tail lamp LH or licence plate lamp) or terminal
No. 13 (tail lamp RH)
NOTE: Before the wiring harness check, check the
intermittent connector D-12, D-16, F-19 and F-28,
and repair that if necessary.

• Check the output lines for open circuit.

Q: Is the check result normal?

YES :

Go to Step 7.

NO :

Repair the wiring harness.

STEP 7. Retest the system
Check that the position lamp and licence plate lamp
illuminate normally.

Q: Is the check result normal?

The lamps illuminate normally at both high and low
beams. :

The trouble can be an intermittent

malfunction (Refer to GROUP 00

− How to

use Troubleshooting/inspection Service
Points

− How to Cope with Intermittent

Malfunction ).

When the position lamps do not illuminate :

Replace the position lamp socket.

When the tail lamps do not illuminate :

Replace

the rear combination lamp socket or the tail
lamp socket.

When the licence plate lamps do not illuminate :

Replace the licence plate lamp socket.

STEP 8. Resistance measurement at the A-35
(position lamp LH) or A-53 (position lamp RH)
headlamp assembly connector, F-23 (LH) or F-08
(RH) rear combination lamp connector, and F-15
(LH) or F-13 (RH) licence plate lamp connector
(1) Disconnect the connector, and measure at the

wiring harness side.

(2) Measure the resistance between the connector of

lamp which does not illuminate and the body

HEADLAMP

CHASSIS ELECTRICAL

54A-121

earth.

• Measure the resistance between the A-35

(LH), A-53 (RH) headlamp assembly connec-
tor terminal No. 6 and the body earth. <Posi-
tion lamp>

• Measure the resistance between the F-23

(LH) and F-08 (RH) rear combination lamp
connector terminal No. 3 and the body earth.

• Measure the resistance between the F-15

(LH), F-13 (RH) licence plate lamp connector
terminal No. 1 and the body earth.

OK: Continuity exists (2

Ω or less)

Q: Is the check result normal?

YES :

Go to Step 10.

NO :

Go to Step 9.

STEP 9. Wiring harness check between the A-35
(position lamp LH) or A-53 (position lamp RH)
headlamp assembly connector terminal No. 6, F-
23 (LH) or F-08 (RH) rear combination lamp
connector terminal No. 3 or F-15 (LH) or F-13
(RH) licence plate lamp connector terminal No. 1
and the body earth

• Check the earth wires for open circuit.

Q: Is the check result normal?

YES :

Go to Step 12.

NO :

Repair the wiring harness.

STEP 10. Connector check: C-304 (position
lamp), C-311 (tail lamp or licence plate lamp)
ETACS-ECU connector

Q: Is the check result normal?

YES :

Go to Step 11.

NO :

Repair the defective connector.

STEP 11. Wiring harness check between the A-35
(position lamp LH) or A-53 (position lamp RH)
headlamp assembly connector terminal No. 4
and C-304 ETACS-ECU connector terminal No. 3
(LH) or terminal No. 7 (RH), F-23 (LH) or F-08 (RH)
rear combination lamp connector terminal No. 2
or F-15 (LH) or F-13 (RH) licence plate lamp
connector terminal No. 2 and C-311 ETACS-ECU
connector terminal No. 10 (tail lamp LH or licence
plate lamp) or terminal No. 13 (tail lamp RH)
NOTE: Before the wiring harness check, check the
intermittent connector D-12, D-16 and F-39, and
repair that if necessary.

• Check the output lines for open circuit.

Q: Is the check result normal?

YES :

Go to Step 12.

NO :

Repair the wiring harness.

STEP 12. Retest the system
Check that the position lamp and licence plate lamp
illuminate normally.

Q: Is the check result normal?

The lamps illuminate normally at both high and low
beams. :

The trouble can be an intermittent

malfunction (Refer to GROUP 00

− How to

use Troubleshooting/inspection Service
Points

− How to Cope with Intermittent

Malfunction ).

When the position lamps do not illuminate :

Replace the position lamp socket.

When the tail lamps do not illuminate :

Replace

the rear combination lamp socket or the tail
lamp socket.

When the licence plate lamps do not illuminate :

Replace the licence plate lamp socket.

Inspection Procedure 10: None of the turn-signal lamps illuminate.

CAUTION

Whenever the ECU is replaced, ensure that the
power supply circuit, the earth circuit and the
communication circuit are normal.
COMMENTS ON TROUBLE SYMPTOM
If all the turn-signal lamps do not illuminate, the igni-
tion switch (IG1), the turn-signal lamp switch input
circuit or the ETACS-ECU may have a problem.

PROBABLE CAUSES

• Malfunction of column switch

• Malfunction of the ETACS-ECU

• Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code
Check if diagnosis code is set to the ETACS-ECU.

Q: Is the diagnosis code set?

YES :

Troubleshoot the ETACS-ECU. Refer to .

NO :

Go to Step 2.