Mitsubishi Evolution X. Manual - part 965

FOG LIGHT

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CHASSIS ELECTRICAL

54A-221

TROUBLE SYMPTOM CHART

M1540401000228

Inspection 
Procedure No.

Trouble symptom

Reference page

1

All the front fog lights do not illuminate normally.

P.54A-222

2

One of the fog lights does not illuminate.

P.54A-228

3

The front fog light indicator does not illuminate normally.

P.54A-232

FOG LIGHT

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CHASSIS ELECTRICAL

54A-222

SYMPTOM PROCEDURES

Inspection Procedure 1: All the front fog lights do not illuminate normally.

CAUTION

Whenever the ECU is replaced, ensure that the power supply circuit, the ground circuit and the com-
munication circuit are normal.

Fog Light and ETACS-ECU Communication Circuit

FUSIBLE
LINK

36

FOG LIGHT
RELAY

RELAY BOX

ENGINE 
COMPARTMENT

ETACS-ECU

FOG LIGHT
(LH)              (RH)

FOG LIGHT

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CHASSIS ELECTRICAL

54A-223

.

CIRCUIT OPERATION

If all the fog lights do not illuminate normally, the 
input signal circuit(s) below or the ETACS-ECU may 
be defective.

• Tail light switch

• Headlight switch

• Fog light switch

• Option coding information

.

TECHNICAL DESCRIPTION (COMMENT)

When the fog lights do not illuminate normally, the 
mentioned input signal circuit(s) or ETACS-ECU may 
be defective.

.

TROUBLESHOOTING HINTS

• Malfunction of the column switch

• Malfunction of the ETACS-ECU

• Damaged harness wires and connectors

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB992006: Extra Fine Probe

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A

AC709111

Connector: A-15X

AH

AC708949AN

Connectors: A-43, A-50

A-43 (B)

A-50 (B)

AC708948AL

Connector: A-54

A-54 (B)

AC708972AP

Connector: C-312

ETACS-ECU

FOG LIGHT

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CHASSIS ELECTRICAL

54A-224

STEP 1. ETACS-ECU coding data check.

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958. Refer to "How to connect 

scan tool (M.U.T.-III) 

P.54A-219

."

(2) Turn the ignition switch to the "ON" position.
(3) Read out the option coding information in ETACS-ECU 

(Refer to GROUP 00, Precautions before service, Coding 
Table 

P.00-39

).

(4) Check that the "Front fog light" is set to "YES."
(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the ETACS-ECU coding data normal?

YES : Go to Step 2.
NO :  Operate scan tool MB991958 to set the option coding 

"Front fog light" to "Yes," and check the trouble 
symptom.

STEP 2. Check that the tail/stop lights and headlights 
operate.
Check that the tail/stop lights and headlights illuminate nor-
mally.
Q: Do the tail/stop lights and headlights operate normally?

YES : Go to Step 3.
NO :  Check the tail/stop lights and the headlights (Refer to 

trouble symptom chart 

P.54A-127

).

STEP 3. Using scan tool MB991958, read the other system 
diagnostic trouble code.
Check if DTC is set to the ETACS-ECU.
(1) Turn the ignition switch to the "ON" position.
(2) Check whether the ETACS-ECU related DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?

YES : Troubleshoot the ETACS-ECU (Refer to ETACS, 

Diagnosis 

P.54A-582

).

NO :  Go to Step 4.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB