KEYLESS ENTRY SYSTEM
BODY42-67
KEYLESS ENTRY SYSTEM
GENERAL DESCRIPTIONBGBJABIE
Antenna and receiver are incorporated in the
ETACS-ECU.
ID code can be registered by using Diagnostic
tool (MUT-III).
Transmitter is a key holder type, which incorpo-
rates lock button, unlock button, trunk button and
panic button
When the transmitter unlock button is pressed
once, the driver's door will be unlocked. If the but-
ton is pressed twice, all the doors will be
unlocked. The adjustment function also allows
you to open all the doors by pressing the unlock
button only once. For further details on using the
multi-center display to adjust the unlock opera-
tion, refer to GROUP 54B, On-vehicle Service
P.54B-486.
When the transmitter is operated, the answer-
back function will work as follows:
The answerback operation can be altered as fol-
lows:NOTE: Enabling/disabling the hazard warning
light flashing, the horn sounding in accordance
with the answerback function. For further details
on using the transmitter to adjust answerback,
P.42-72 see the section below. For further details
on using the multi-center display to adjust
answerback, refer to GROUP 54B, On-vehicle
Service P.54B-486. ITEM OPERATION
DOORS LOCKED DOORS UNLOCKED
Dome light Flashes once Illuminates for 15 seconds
Turn-signal lights (RH and LH) Flashes once Flashes twice
Horn Sounds once when the lock button
is pressed with all the doors locked-
ITEM ADJUSTMENT ITEM ADJUSTMENT DETAIL
Keyless entry system
confirmation by turn
signal lightsAdjustment of hazard answerback
when the transmitter is used to
lock doorsWhen adjusting hazard answerback after the
doors are locked with the transmitter, the
following flashing conditions can be selected.
a. Flash (default)
b. No flash
Adjustment of hazard answerback
when the transmitter is used to
unlock doorsWhen adjusting hazard answerback after the
doors are unlocked with the transmitter, the
following flashing conditions can be selected.
a. Flash (default)
b. No flash
Keyless entry system
confirmation by hornAdjustment of horn answerback
when the transmitter is used to
lock doorsWhen adjusting horn answerback after the
doors are locked with the transmitter, the
following horn conditions can be selected.
a. Horn sounds
b. Horn sounds if doors are already locked
(default)
c. Horn does not sound
KEYLESS ENTRY SYSTEM
BODY42-68
If none of the doors is opened or the ignition key
is not inserted in the ignition switch within 30 sec-
onds after the doors are unlocked using the
transmitter, the ETACS-ECU will relock the doors
automatically. This is called "Timer lock function."
This timer lock function prevents accidental
unlocking of doors. The adjustment function
allows you to change the timer lock period from 30 seconds (default setting) to 60, 120 or 180
seconds. For further details on using the
multi-center display (middle grade type) to adjust
the timer lock period, refer to GROUP 54B,
On-vehicle Service P.54B-486.
NOTE: The timer lock period begins when the doors
are unlocked, and ends when the doors is relocked
automatically.
KEYLESS ENTRY SYSTEM DIAGNOSISBGBCJGAI
The keyless entry system is controlled by the Simpli-
fied Wiring System (SWS). Refer to GROUP 54B,
SWS Diagnosis P.54B-57.
SPECIAL TOOLBGBBBGDH
TOOL TOOL NUMBER AND
NAMESUPERSESSION APPLICATION
A: MB991824
B: MB991827
C: MB991910
D: MB991911
E: MB991914
F: MB991825
G: MB991826
MUT-III Sub Assembly
A: Vehicle communication
interface (V.C.I.)
B: MUT-III USB cable
C: MUT-III main harness A
(Vehicles with CAN
communication system)
D: MUT-III main harness B
(Vehicles without CAN
communication system)
E: MUT-III main harness C
(for Daimler Chrysler
models only)
F: MUT-III measurement
adapter
G: MUT-III trigger harnessMB991824-KIT
NOTE: G: MB991826
MUT-III Trigger Harness is
not necessary when
pushing V.C.I. ENTER key.For registration of secret
code
For vehicles with CAN
communication, use
MUT-III main harness A to
send simulated vehicle
speed. If you connect
MUT-III main harness B
instead, the CAN
communication does not
function correctly.
KEYLESS ENTRY SYSTEM
BODY42-69
ON-VEHICLE SERVICE
INSPECTIONM1428003800089
KEY TRANSMITTER BATTERY CHECK
Measure the voltage of the battery. If the voltage of the battery
is not within the standard value, replace the battery.
Standard value:2.5
3.2 V
KEYLESS ENTRY SYSTEM
BODY42-70
HOW TO REPLACE THE TRANSMITTER
BATTERY
BGBCHGFB
Do not allow water or dust to enter the inside of the trans-
mitter when it is opened. Also, do not touch the precision
electronic device.
1. Insert a flat blade screwdriver (cloth covered) at the base of
the key transmitter case (in slot) and twist, to open the case,
as shown in figure 1, (be careful not to lose switch button
pads when opening).
2. Remove internal case and insert a flat blade screwdriver
(cloth covered) at the switch assembly (in slot) as shown in
figure 2 and twist, to open the internal case (be careful not
to lose battery when opening).
Battery required for replacement: Coin type battery
CR1620 (3V)
3. Install a battery with its (+) side face-down, at base of
switch, and reassemble the key transmitter.
4. Verify that the keyless entry system operates.
KEYLESS ENTRY SYSTEM
BODY42-71
KEYLESS ENTRY SYSTEM INSPECTIONBGBHCDAE
Check the following items. If defective, refer to GROUP 54B,
SWS Diagnosis P.54B-10).
1. Operate the transmitter to check that the doors can be
locked and unlocked.
NOTE: The adjustment function allows you to change the
unlock operation setting as follows. Prior to that check, con-
firm which setting is activated.
.
a. When the unlock button is pressed once, the driver's
door will be unlocked. Then when the button is pressed
once again, all the doors will be opened (initial setting).
b. When the unlock button is pressed only once, all the
doors will be opened.
2. Press the trunk lid button of transmitter twice (press once,
and then press again within 5 seconds) and confirm that the
trunk lid opens.
3. Operate the transmitter to check that the answerback
function works in response to doors locking/unlocking.
NOTE: The adjustment function allows you to change the
hazard answerback setting as follows. Prior to that check,
confirm which setting is activated.
.
a. Turn-signal lights: Flash once when doors are locked,
and twice when unlocked (initial setting)
b. Turn-signal lights: Flash once when doors are locked,
but does not flash when unlocked.
c. Turn-signal lights: Do not flash when doors are locked,
but flash twice when unlocked.
d. Turn-signal lights: Do not flash when doors are locked
and unlocked.
NOTE: The adjustment function allows you to change the
horn answerback setting as follows. Prior to that check, con-
firm which setting is activated.
.
a. Horn: Sounds once when the lock button is pressed.
b. Horn: Sounds once when the lock button is pressed (ini-
tial setting).
c. Horn: Does not sound.
KEYLESS ENTRY SYSTEM TIMER LOCK
FUNCTION INSPECTION
BGBEBDIA
If the doors are not locked within 30 seconds after the unlock
button is pressed, refer to GROUP 54B, SWS Diagnosis
P.54B-10.
NOTE: If either of the doors is opened or the key is inserted in
the ignition switch within that 30-second period, the timer lock
function will be cancelled.
KEYLESS ENTRY SYSTEM
BODY42-72
NOTE: The adjustment function allows you to change the timer
lock period from 30 seconds (initial setting) to 60, 120 or 180
seconds. Prior to this inspection, confirm which setting is acti-
vated.
ENABLING/DISABLING THE ANSWERBACK
FUNCTION
BGBDGCGD
When the doors are locked or unlocked by using the transmit-
ter, the dome light will flash/illuminate, the turn-signal lights will
flash (hazard answerback), or the horn will sound (horn
answerback) to inform the driver.
The hazard answerback and horn answerback functions can be
enabled or disabled according to the following procedure:
ENABLING/DISABLING THE HAZARD
ANSWERBACK FUNCTION
.
How to adjust hazard answerback when the trans-
mitter is used to lock doors
1. Remove the ignition key.
2. Push the ”unlock” button and then push the ”lock“ button
within 4 seconds to 10 seconds.
3. Release the ”lock” button within 10 seconds after Step 2 and
then release the “unlock” button. The ETACS-ECU tone
alarm will sound, indicating that the hazard answerback
function can be enabled or disabled when the doors are
locked.
Enable the hazard answerback function when the
doors are locked: The ETACS-ECU tone alarm will
sound once.
Disable the hazard answerback function when the
doors are locked: The ETACS-ECU tone alarm will
sound twice.
.
How to adjust hazard answerback when the
transmitter is used to unlock doors
1. Remove the ignition key.
2. Push the ”unlock” button and then push the ”lock“ button
within 4 seconds to 10 seconds.
3. Release the ”lock” button within 10 seconds after Step 2 and
then release the “unlock” button. The ETACS-ECU tone
alarm will sound, indicating that the hazard answerback
function can be enabled or disabled when the door are
unlocked.
Enable the hazard answerback function when the
doors are unlocked: The ETACS-ECU tone alarm
will sound once.
Disable the hazard answerback function when the
doors are unlocked: The ETACS-ECU tone alarm
will sound twice.
KEYLESS ENTRY SYSTEM
BODY42-73
ENABLING/DISABLING THE HORN
ANSWERBACK FUNCTION
.
1. Remove the ignition key.
2. Push the ”unlock” button and then push the ”lock“ button
within 4 seconds to 10 seconds.
3. Release the ”lock” button within 10 seconds after Step 2 and
then release the “unlock” button. The ETACS-ECU tone
alarm will sound, indicating that the horn answerback
function can be enabled or disabled.
Enable the horn answerback function*: The
ETACS-ECU tone alarm will sound once.
Disable the horn answerback function: The
ETACS-ECU tone alarm will sound twice.
Enable the horn answerback function**: The
ETACS-ECU tone alarm will sound three times.
NOTE: .
*: The horn will sound if "LOCK" button is pressed with the
doors locked.
**: The horn will sound if the doors are locked with the key-
less entry system.
HOW TO REGISTER SECRET CODEBGBHCCCB
Required Special Tools:
: MUT-III Sub Assembly
MB991824: Vehicle Communication Interface (V.C.I.)
MB991910: MUT-III Main harness A
Each individual secret code is registered inside the transmitter,
and so it is necessary to resister these codes with the
EEPROM inside the receiver in the following cases.
When the transmitter or ETACS-ECU is replaced
If more transmitters are to be used
If it appears that a problem is occurring because of faulty
registration of a code.
A maximum of four different codes can be stored in the
EEPROM memory (four different transmitters can be used).
When the code for the first transmitter is registered, the previ-
ously registered codes for all transmitters are cleared. There-
fore, if you are using four transmitters or are adding more
transmitters, the codes for all transmitters must be registered at
the same time.
WHEN SPECIAL TOOL MB991824 (V.C.I.) IS USED
.
1. Check that the doors lock normally when the key is used.
2. Insert the ignition key.
KEYLESS ENTRY SYSTEM
BODY42-74
To prevent damage to special tool MB991824 (V.C.I.),
always turn the ignition switch to “LOCK” (OFF) position
before connecting or disconnecting special tool MB991824
(V.C.I.).
3. Connect special tool MB991824 (V.C.I.) to the data link
connector.
4. Press the hazard warning light switch six times within 10
seconds.
NOTE: When the hazard warning light switch has been
pressed six times, the ETACS-ECU locks and unlocks the
doors automatically once. The ETACS-ECU is ready to reg-
ister an encrypted code.
NOTE: The hazard warning light switch is a toggle switch.
5. Press the transmitter button, and then press it two times
within 10 seconds of the first press. This will register the
code.
6. When the encrypted code has been registered, the
ETACS-ECU locks and unlocks the doors automatically
once.
7. If you are using two or more transmitters or have added a
second transmitter, the next transmitter should be registered
within one minute after registering the code for the previous
transmitter. The registration procedure is common for all the
transmitter.
8. Registration mode will be canceled under the following
conditions:
When the secret code for four transmitters has been regis-
tered;
When passing one minute after finishing the registration of
all transmitters;
When special tool MB991824 (V.C.I.) is disconnected;
When the key is removed from the key cylinder;
9. After the registration is completed, remove the ignition key
and close all the doors, and then check that the keyless
entry system operates normally.