Mitsubishi Evolution X. Manual — part 622

DIAGNOSIS

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WIRELESS CONTROL MODULE (WCM)

42C-105

Inspection Procedure 8: The trunk is not opened when the keyless entry transmitter "TRUNK" button
is operated.

CAUTION

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

AC708974

ETACS-ECU

BLA

CK

BLA

CK

GREEN

WHITE

-BLUE

BLA

CK

-BLUE

YELLO

W

-GREEN

TRANSMITTER"TRUNK"BUTTON

INPUT SIGNAL

WIRELESS

CONTROL

MODULE

INTERFACE

CIRCUIT

CAN DRIVE

CIRCUIT

JOINT

CONNECTOR

(CAN1)

Transmitter "TRUNK" Input Signal

AB

JOINT
CONNECTOR
(6)

RECEIVER

RECEIVER
ANTENNA
ASSEMBLY

RED

RED

GREEN -RED

GREEN -RED

YELLOW

-GREEN

YELLOW

-GRAY

YELLOW

-GRAY

BROWN -WHITE

BROWN -WHITE

RED- WHITE

RED- BLA

CK

RED- WHITE

RED- WHITE

RED- WHITE

RED

GREEN -RED

BROWN -WHITE

RED- WHITE

TRUNK

LID OPEN

RELAY

TRUNK LID

LATCH

DIAGNOSIS

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WIRELESS CONTROL MODULE (WCM)

42C-106

.

TECHNICAL DESCRIPTION (COMMENT)

The receiver antenna assembly receives the trunk
signals from the transmitter, and sends them to the
WCM, and further to the ETACS-ECU. Then the
ETACS-ECU determines to actuate the trunk open
function of the keyless entry system.

.

TROUBLESHOOTING HINTS

• The keyless entry transmitter may be defective

• The receiver antenna assembly may be defective

• The WCM may be defective

• The ETACS-ECU may be defective

• The wiring harness or connectors may have

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

DIAGNOSIS

Required Special Tools:

• MB992006: Extra fine probe

• MB991223: Harness set

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

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

• MB991827 M.U.T.-III USB Cable

• MB991910 M.U.T.-III Main Harness A

STEP 1. Check the operation of the keyless entry system.
Operate the transmitter and check that all doors lock and
unlock.
Q: Is the check result normal?

YES : Go to Step 2.
NO : Refer to inspection procedure 5: "Keyless entry

system does not work

P.42C-93

."

AC708972AC

Connector: C-311

ETACS-ECU

AC708955AL

Connector: D-17

D-17 (BR)

AC708970AD

Connectors: F-19, F-27

F-27

F-19

DIAGNOSIS

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WIRELESS CONTROL MODULE (WCM)

42C-107

STEP 2. Using scan tool MB991958, check for 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.42C-6

."

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

YES : Diagnose the WCM. Refer to Diagnostic trouble code

chart

P.42C-14

.

NO : Go to Step 3.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

DIAGNOSIS

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WIRELESS CONTROL MODULE (WCM)

42C-108

STEP 3. Using scan tool MB991958, check pulse check.
Check the signals related to the keyless entry system opera-
tion.

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 the

Scan Tool (M.U.T.-III)

P.42C-6

."

(2) Confirm the ETACS pulse check.

• Remove the ignition key from the ignition key cylinder.

OK: The scan tool (M.U.T.-III) tone alarm sounds.

Q: Is the check result normal?

YES : Go to Step 4.
NO : Refer to "Signals from transmitter switches are not

received

P.42C-111

."

STEP 4. Check trunk lid latch connector F-19 and
ETACS-ECU connector C-311 for loose, corroded or
damaged terminals, or terminals pushed back in the
connector.
Q: Is trunk lid latch connector F-19 and ETACS-ECU

connector C-311 in good condition?
YES : Go to Step 5.
NO : Repair or replace the damaged component(s). Refer

to GROUP 00E, Harness Connector Inspection

P.00E-2

.

Item name

Conditions

Transmitter switch

Turn the switch ON/OFF.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB