Mitsubishi Montero Sport (2004+). Manual - part 477

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ON-VEHICLE SERVICE

HOW TO REPLACE THE TRANSMITTER 
BATTERY

M1428000900140

CAUTION

Do not allow water or dust to enter the inside of the trans-
mitter when it is open. Also, do not touch the electronic 
device inside.
1. Remove the set screw to remove the battery from the 

transmitter.

2. Install a battery with its (+) side face-down.

Battery required for replacement: Coin type battery 
CR2032

3. Insert the claw first, and assemble the transmitter.
4. Verify that the keyless entry system operates.

SECRET CODE REGISTRATION METHOD

M1428001000407

Required Special Tools:

• MB991529: Diagnostic trouble code check harness

•  MB991958: Scan Tool (MUT-III Sub Assembly)

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

• MB991911: MUT-III Main Harness B

Each individual secret code is registered inside the transmitter, 
and so it is necessary to resister these codes with the 
EEPROM inside the keyless entry receiver-ECU in the follow-
ing cases.

• When the transmitter or keyless entry receiver-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 two different code can be stored in the memory 
area of the EEPROM (two different transmitters can be used). 
When the code for the first transmitter is registered, the previ-
ously registered codes for two transmitters are cleared. There-
fore, if you are using more than two transmitters or are adding a 
second transmitter, the codes for all the transmitters must be 
registered at the same time.

AC000123 AB

BATTERY

CLAW

SCREW

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WHEN SPECIAL TOOL MB991529 IS USED

CAUTION

When the equipment, which operates from the other 
makes of audio or cigarette lighter has been installed, the 
power supply (ACC) may not be switched off for a while 
even if the ignition switch  is turned to the "OFF" position. 
Therefore, if the encrypted code registration mode of 
transmitter is not entered, remove the power supply of the 
equipment, which operates from the other makes of audio 
or cigarette lighter and register it.
1. Check that the doors lock normally when the key is used.

CAUTION

Turn the ignition switch to the "LOCK" (OFF) position and 
then connect data link connector terminal 1 to ground.
2. Connect the data link connector terminal 1 to ground.

NOTE: Connecting terminal 1 of the data link connector to 
ground will put the system in secret code registration 
standby mode.

3. Within 10 seconds after connecting data link connector 

terminal 1 to ground turn the ignition switch to "ACC" for 1 
second and then to "OFF" for 1 second; repeat this 
procedure three times.
NOTE: The doors will lock and unlock once at this time and 
the system will switch to registration mode.

4. Press the transmitter switch, and then press it two times 

within 10 seconds of the first press. This will register the 
code.

5. After registration is completed, the code will be automatically 

locked and unlocked once.

6. If you are using two transmitters or have added a second 

transmitter, the same registration procedure should be 
carried out for the second transmitter, and it should be 
carried out within one minute after registration of the code 
for the first transmitter has been completed. After the 
second registration is completed, the doors will be 
automatically locked and unlocked once.

7. Registration mode will be terminated under the following 

condition:

• When the secret codes for two transmitters have been reg-

istered.

• When one minute has passed after registration mode 

started.

• When the data link connector terminal 1 to ground is dis-

connected.

• If the ignition switch is turned to "ON".

AC309159AB

MB991529

AC005054

IGNITION SWITCH

ACC

OFF

1s 1s 1s 1s 1s 1s

WITHIN 10 SECONDS

AC

GROUND

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8. After registration mode has been completed, carry out the 

following to make sure that the keyless entry system 
operations.

• Pull the ignition key out.

• Close the all doors.

WHEN SPECIAL TOOL MB991824 (V.C.I.) IS USED

CAUTION

When the equipment, which operates from the other 
makes of audio or cigarette lighter has been installed, the 
power supply (ACC) may not be switched off for a while 
even if the ignition switch  is turned to the "OFF" position. 
Therefore, if the encrypted code registration mode of 
transmitter is not entered, remove the power supply of the 
equipment, which operates from the other makes of audio 
or cigarette lighter and register it.
1. Check that the doors lock normally when the key is used.

CAUTION

Turn the ignition switch to the "LOCK" (OFF) position and 
then connect special tool MB991824 (V.C.I.) to the data link 
connector.
2. Connect special tool MB991824 (V.C.I.) to the data link 

connector.

3. Within 10 seconds after turning the V.C.I. power supply 

switch to the "ON" position, turn the ignition switch to "ACC" 
for 1 second and then to "OFF" for 1 second; repeat this 
procedure three times.
NOTE: The doors will lock and unlock once at this time and 
the system will switch to registration mode.

4. Press the transmitter switch, and then press it two times 

within 10 seconds of the first press. This will register the 
code.

5. After registration is completed, the code will be automatically 

locked and unlocked once.

AC309188AB

MB991911

MB991824 

16-PIN

AC005054

IGNITION SWITCH

ACC

OFF

1s 1s 1s 1s 1s 1s

WITHIN 10 SECONDS

AD

CONNECT V.C.I. AND TURN 
THE  V.C.I.  POWER SUPPLY 
SWITCH ON.

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6. If you are using two transmitters or have added a second 

transmitter, the same registration procedure should be 
carried out for the second transmitter, and it should be 
carried out within one minute after registration of the code 
for the first transmitter has been completed. After the 
second registration is completed, the doors will be 
automatically locked and unlocked once.

7. Registration mode will be terminated under the following 

condition:

• When the secret codes for two transmitters have been reg-

istered.

• When one minute has passed after registration mode 

started.

• When special tool MB991824 (V.C.I.) is disconnected from 

the data link connector.

• If the ignition switch is turned to "ON".

8. After registration mode has been completed, carry out the 

following to make sure that the keyless entry system 
operations.

• Pull the ignition key out.

• Close the all doors.

ETACS-ECU FUNCTION ADJUSTMENT PROCEDURE

M1428003700037

The following functions can be adjusted by operating 
input swatches. The adjustments will be stored in the 
ECU memory even after a battery cable is discon-
nected:

• Switching of keyless entry answerback function. 

(From activation to deactivation, or vice versa)

• Initialization the above function (From deactiva-

tion to activation)

1. Entry conditions the adjustment mode

The ETACS-ECU sounds a tone alarm once when 
all of the following conditions are satisfied, and 
then enters the adjustment mode:

• Data link control: "ON" [Connect scan tool 

MB991958 (MUT-III sub assembly) or ground the 
data link connector No.1 terminal.]

• Key reminder switch: "OFF"

• Ignition switch: "OFF"

• Door switch: "OFF" (Close the door.)

• If all of the conditions above are satisfied, the tail-

light switch will be turned on for more than 10 
seconds.

2. Exit conditions from the adjustment mode

The ETACS-ECU cancels the adjustment mode 
when any of the following conditions is satisfied:

• Diagnosis control: "OFF" [Disconnect scan tool 

MB991958 (MUT-III sub assembly) or disconnect 
the data link connector No.1 terminal from the 
ground.]

• Key reminder switch: "ON" (Pull out the ignition 

key.)

• Ignition switch: Other than "OFF"

• Door switch: "ON" (Open the door.)

• After the ETACS-ECU has entered the adjust-

ment mode, no adjustment is made within 3 min-
utes (If any adjustment is made within 3 minutes, 
the ETACS-ECU monitors a adjustment operation 
for other 3 minutes.)

• Other warning tone alarm sounds