Mitsubishi Evolution X. Manual - part 962

REAR COMBINATION LIGHT

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CHASSIS ELECTRICAL

54A-209

STEP 7. Using scan tool MB991958, Check whether the 
diagnostic trouble code is reset.

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-194

."

(2) Turn the ignition switch to the "ON" position.
(3) Erase the DTC.
(4) Turn the ignition switch from "LOCK" (OFF) position to "ON" 

position.

(5) Check if DTC is set.
Q: Is the DTC set?

YES : Replace the ETACS-ECU.
NO :  The procedure is complete.

TROUBLE SYMPTOM CHART

M1541401000243

SYMPTOM PROCEDURES

Inspection Procedure 1: All the taillights do not illuminate.

CAUTION

Before replacing the ECU, ensure that the power 
supply circuit, the ground circuit and the com-
munication circuit are normal.

.

TECHNICAL DESCRIPTION (COMMENT)

If all the taillights do not illuminate normally, the tail-
light switch input circuit or ETACS-ECU may have a 
problem. 

.

TROUBLESHOOTING HINTS

• Malfunction of column switch

• Malfunction of the ETACS-ECU

• The wiring harness or connectors may have 

loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

Inspection 
Procedure No.

Trouble symptom

Reference page

1

All the taillights do not illuminate.

P.54A-209

2

One of the headlights does not illuminate.

P.54A-212

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DIAGNOSIS

Required Special Tools:

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

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A (Vehicles with 

CAN communication system)

STEP 1. License plate light operation check
Check that the license plate light illuminates normally.
Q: Does license plate light work normally?

YES : Go to Step 2.
NO :  Replace the ETACS-ECU.

STEP 2. Using scan tool MB991958, read the diagnostic 
trouble code. 

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-194

."

(2) Turn the ignition switch to the "ON" position.
(3) Check whether the ETACS-ECU related DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?

YES : Diagnose the ETACS-ECU. Refer to ETACS, 

Diagnosis 

P.54A-582

.

NO :  Go to Step 3.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

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CHASSIS ELECTRICAL

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STEP 3. Using scan tool MB991958, check data list. 
Use the ETACS-ECU data list to check the signals related to 
the taillight illumination.

• Turn the ignition switch to the "ACC" position.

• Turn the taillight switch to the "ON" position.

Q: Does scan tool MB991958 display the items "Taillight" 

as normal condition?
YES : Go to Step 4.
NO :  Troubleshoot the ETACS-ECU (Refer to 

P.54A-639

).

STEP 4. Retest the system
Check that the taillight illuminates normally.
Q: Does the taillight work normally?

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 

P.00-15

).

NO :  Replace the ETACS-ECU.

Item No.

Item name

Normal 
conditions

Item 218

Taillight

ON

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Inspection Procedure 2: One of the headlights does not illuminate.

.

Taillight Circuit

REAR
COMBINATION
LIGHT
(LH)                     (RH)

ETACS-ECU

JOINT
CONNECTOR

TAILLIGHT CONTROL CIRCUIT

AC608145

BT

Connector: C-38

AC608152 AK

Connector: C-311

Junction block

AC608166

AM

Connector: D-11

AC608171AP

Connectors: F-06, F-20

F-06

F-20