The wireless control module (WCM) is a system that
integrates the keyless entry function, with which
remote operation (opening/closing of all doors, open-
ing of trunk lid, and operation of warning function that
warns a person who intends to damage the vehicle

), can be performed by operating the lock/unlock

button, trunk lid button or panic button on the ignition
key (transmitter). Also, WCM incorporates the immo-
bilizer function, which prohibits the starting of engine
using an unauthorized key, and the tire pressure
monitoring system (TPMS), which issues a warning
to a driver by illuminating or flashing the warning light
if an abnormality to the tire pressure or the system
error is detected. WCM has the following features:

• The ignition key has an indicator light that

enables the driver to check if the signal is trans-
mitted correctly or if the battery in the key is dis-
charged.

• Each vehicle is provided with two ignition keys,

and up to eight ignition keys can be registered.

• Settings of the keyless entry function can be

adjusted using a customization function.

NOTE:

: Horn sounds, and headlights and taillights

flash.

CONSTRUCTION DIAGRAM

AC709254

LOW

TIRE PRESSURE

Multi information display
(Built in combination meter)

TPMS
warning light

ETACS-ECU

WCM

Lock button

Unlock button

Ignition key

ECM

Indicator light

TPMS transmitter
(Tire pressure sensor)

ASC-ECU

Trunk lid button

Panic button

Reciever antenna assembly

GENERAL INFORMATION

TSB Revision

WIRELESS CONTROL MODULE (WCM)

42C-3

Main components and functions

NOTE:

•

: Illuminates for tire pressure warning.

•

: Flashes for about 1 minute and then continuously illuminated for TPMS malfunction warning.

Parts name

Functional description

WCM

Controls the keyless entry functions, TPMS functions and starting of the engine
by using the following communications.

• Communications with ETACS-ECU, ECM, ASC-ECU and combination

meter via CAN

• Wireless communication with the ignition key (transponder)

• Wireless communication with the ignition key (transmitter) via the receiver

antenna assembly

Reciever antenna
assembly

Receives the operation signals from the lock/unlock buttons, trunk lid button,
and panic button on the ignition key (transmitter) as well as the tire pressure
signal from the TPMS transmitter. Then, transmits them to WCM.

Ignition key

The ignition key also sends signals to reciever antenna assembly when the
lock/unlock/trunk lid button and the panic button on it are operated.

Combination meter (Multi
information display, TPMS
warning light)

Communicates with WCM via CAN. Send ignition switch status. Receives the
warning request or warning information about TPMS from WCM, activates

the

TPMS warning iight. Warning symbol and message is additionally displayed on
the multi information display.

ETACS-ECU

Communicates with WCM via CAN. By the door lock/unlock request, trunk lid
open request, or panic alarm request from WCM, ETACS-ECU outputs the
lock/unlock signal, trunk lid open signal, or panic alarm signal. When the door
lock/unlock signal is output, ETACS-ECU flashes or illuminates the turn signal
light and dome light to notify that the lock/unlock operation is performed.

ASC-ECU

Communicates with WCM via CAN. Sends the vehicle speed data.

ECM

Communication with WCM via CAN. Send atmospheric pressure data..

TPMS transmitter

Measure tire pressure directly, then send radio frequency signal to receiver
antenna assembly.

SERVICE SPECIFICATIONS

TSB Revision

WIRELESS CONTROL MODULE (WCM)

42C-4

System configuration

NOTE: In case of replacement of WCM, all keyless
ID, key ID and tire pressure sensor ID should be
re-registered using scan tool MB991958 (M.U.T.-III
sub-assembly).

SERVICE SPECIFICATIONS

M1427501500028

AC709230

Door lock actuator

ETACS-ECU

Turn-signal light

Wireless control module
(WCM)

ECM

Combination meter
(Multi information display,
TPMS warning light)

Lock button

Unlock button

Indicator light

CAN-B
communi-
cation

CAN-C comm-
unication

Trunk lid latch

Ignition key

Radio
frequency
signal
(transponder)

Front tire (LH)

Front tire (RH)

Rear tire (LH)

Rear tire (RH)

TPMS transmitter

CPU

Transmission
circuit

Antenna

Pressure
sensor

Acc.
sensor

Battery

ASC-ECU

Dome light,
Ignition key cylinder
illumination light

Horn

Panic button

Trunk lid button

Radio
frequency
signal
(transmitter)

Reciever antenna
assembly

Radio
frequency
signal (transmittter)

Head light,
Tail light

Item

Standard value

Voltage of transmitter battery (V)

2.5 ~ 3.2

Content .. 594 595 596 597 ..