Page 393 of 1501

1) Using ohmmeter, check for continuity between specified
rear differential lock switch terminals with switch in specified
positions. See WIRING DIAGRAMS.
2) With lock switch in ON position, continuity should exist
between terminals No. 2 and 5. With lock switch in OFF position,
continuity should exist between terminals No. 2 and 3.
3) Continuity should also exist between terminals No. 1 and 6
with lock switch in ON or OFF position. If continuity is not as
specified, replace lock switch.
REAR DIFFERENTIAL LOCK SYSTEM AIR LEAKAGE CHECK
NOTE: DO NOT apply more pressure than required to bring pressure
gauge reading to about 5 psi (.35 kg/cm ).
1) Remove rear differential lock air pump and remove air hose
from air pump. Connect a pressure gauge and air regulator (for
adjusting compressed air pressure) to air hose. Using air regulator,
adjust compressed air pressure until pressure gauge indicates about 5
psi (.35 kg/cm
).
2) Shut off air valve. Wait about 10 minutes and check if air
pressure has dropped. If air pressure has dropped, air hose is not
leaking.
REMOVAL & INSTALLATION
REAR DIFFERENTIAL LOCK AIR PUMP
Removal & Installation
Remove rear seat. Remove bracket from rear differential lock
air pump and remove air pump. Disconnect air hoses from air pump.
Disconnect electrical connector from air pump. To install, reverse
removal procedure.
REAR DIFFERENTIAL LOCK CONTROL UNIT
Removal & Installation
Remove left side lower quarter trim panel in rear
compartment. Remove rear differential lock control unit. Disconnect
electrical connector from control unit. To install, reverse removal
procedure.
WIRING DIAGRAMS
Page 394 of 1501
Fig. 3: Rear Differential Lock System Wiring Diagram (1997 Montero)
Page 395 of 1501
Fig. 4: Rear Differential Lock System Wiring Diagram (1998 Montero)
Page 396 of 1501
Fig. 5: Rear Differential Lock System Wiring Diagram (1998
Montero Sport)
Page 397 of 1501

DOOR LOCKS - POWER & KEYLESS ENTRY
1998 Mitsubishi Montero
1998 ACCESSORIES & EQUIPMENT
Mitsubishi - Keyless Entry & Power Door Locks
Montero & 3000GT
DESCRIPTION & OPERATION
On 3000GT, power door locks are controlled by driver or
passenger switches which send signals to Electronic Timer Alarm
Control System (ETACS) ECU. ETACS-ECU sends appropriate signals to
individual door lock actuators through individual relays.
The following features are incorporated in power door lock
systems that have an ETACS-ECU:
* Once locked door is closed, system will unlock door if key
remains in ignition switch.
* Continuous switching between lock and unlock of door will
disable system for about one minute.
On Montero, power door lock actuator receives signal from
individual control relay that is operated by a switch incorporated in
actuator. On all models, all door locks are actuated with operation of
one lock.
Montero and 3000GT offer optional keyless entry system. Use
of a 2-button portable remote control operates door locks within a
range of 13 ft. (4 m). Dome light flashes twice when doors are locked
and illuminates for 3 seconds when doors are unlocked. If, after 30
seconds, door(s) have not been opened when unlocked with keyless entry\
system, doors will relock.
COMPONENT LOCATIONS
COMPONENT LOCATIONS TABLE \
\
\
\
\
\
Component Location
ETACS-ECU
3000GT ........................ Behind Left Side Of Dash
Data Link Connector (DLC) ....... Under Left Side Of Dash,
Below Steering Column
Door Lock Actuator ...................... Inside Each Door
Door Lock Relay
Montero ....................... Behind Left Side Of Dash
3000GT
No. 1 ........................ Under Left Side Of Dash
No. 2 ................. Behind Left Rear Quarter Panel
Power Door Lock Control Unit
Montero
W/O RKE .................... Behind Left Side Of Dash,
Behind Speaker
Receiver
3000GT ................. Behind Right Rear Quarter Panel
Remote Keyless Entry (RKE)
Control Unit
Montero ............... Behind Right Rear Quarter Panel
3000GT ................. Behind Left Rear Quarter Panel
\
\
\
\
\
\
Page 398 of 1501

TRANSMITTER PROGRAMMING
NOTE: Transmitter programming should be performed only after
verifying that door lock operates normally using key.
NOTE: Ensure ignition is off when connecting or disconnecting scan
tool.
Using Scan Tool (Montero & 3000GT)
1) Connect scan tool to DLC. Close all doors. Turn ignition
switch to ACC position, then to OFF position. Press desired
transmitter switches (secret code), then press twice within 10 seconds\
to register code.
2) Lock and unlock door once. If there are 2 transmitters,
program the first, then the second transmitter using the same
procedure within one minute. After completing the second programming,
lock and unlock door once.
3) Programming mode is finalized when programming of second
transmitter secret code is complete, one minute after setting secret
code, when scan tool is disconnected, when ignition is turned on or
when any door is opened.
Without Scan Tool (Montero)
1) Move code registration switch on RKE control unit to SET I
position. Press the LOCK or UNLOCK button on transmitter. Move code
registration switch on control unit to FIX position.
2) Confirm that keyless entry system operates normally. If
system does not operate normally, repeat step 1). If 2 transmitters
are used, register code on SET II position on RKE control unit and set
in same manner as the first transmitter.
TROUBLE SHOOTING
POWER DOOR LOCK INOPERATIVE
Operate door lock(s) with ignition switch in OFF position. If\
door lock(s) do not operate, check for following possible causes:
* Burned fuse, circuit breaker or fusible link caused by short
to body ground.
* Wire connector, or pin inside connector, disengaged at any
connector or component in system.
* Defective ETACS-ECU (if equipped).
* Defective door lock switch, relay or actuator.
* Subfreezing weather conditions, mechanical failure, or
corroded or misaligned assemblies.
KEY REMINDER SYSTEM INOPERATIVE (ETACS-ECU CONTROLLED SYSTEM)
With key inserted in ignition switch, lock driver's or
passenger's door and close door. If door locks do not unlock, check
for following possible causes:
* Defective key reminder switch or no input signal to
ETACS-ECU.
* Defective front door switch or no input signal to ETACS-ECU.
* Defective vehicle speed sensor or no input signal to
ETACS-ECU.
INPUT SIGNAL
Page 399 of 1501

Scan Tool Method (3000GT)
Turn ignition off. Connect scan tool to DLC. Follow scan tool
manufacturer's instructions. Turn ignition on. Perform ON/OFF
operation of each door lock or power window switch. If scan tool
buzzer sounds once, ECU input signal to corresponding switch circuit
is normal.
Voltmeter Method (3000GT)
Using Diagnostic Trouble Code Check Harness (MB991529),
connect harness to DLC terminals No. 4 and 5. Connect voltmeter to
harness. Turn ignition on. Perform ON/OFF operation of each door lock
or power window switch. If voltmeter pointer moves once, ECU input
signal from corresponding switch circuit is normal.
COMPONENT TESTS
* PLEASE READ THIS FIRST *
NOTE: If after all testing procedures are completed, system is not
functioning properly, substitute with a known-good ETACS-ECU
and retest.
DOOR LOCK ACTUATOR
Left Front Door (Montero & 3000GT)
1) Access left front door lock actuator. See
DOOR LOCK ACTUATOR R & I under REMOVAL & INSTALLATION. Disconnect
harness connector. Set actuator in LOCK position. Connect positive
lead of 12-volt power source to actuator terminal No. 1 (Blue/Red
wire) on Montero or terminal No. 3 (Blue/Red wire) on 3000GT. See
WIRING DIAGRAMS . Actuator should move to UNLOCK position when terminal
No. 3 (White/Black wire) on Montero or terminal No. 1 (Blue/Black
wire) on 3000GT is connected to ground.
2) With actuator set in UNLOCK position, connect positive
lead of 12-volt power source to actuator terminal No. 3 (White/Black
wire) on Montero or terminal No. 1 (Blue/Black wire) on 3000GT. See
WIRING DIAGRAMS . Actuator should move to LOCK position when terminal
No. 1 (Blue/Red wire) on Montero or terminal No. 3 (Blue/Red wire) o\
n
3000GT is connected to ground.
3) On 3000GT, check for continuity between actuator terminals
No. 2 (Brown/Yellow wire) and No. 4 (Black wire). See WIRING DIAGRAMS.
Continuity should be present with actuator set in UNLOCK position.
Continuity should not be present with actuator set to LOCK position.
Right Front Door (Montero & 3000GT)
1) Access right front door lock actuator. See
DOOR LOCK ACTUATOR R & I under REMOVAL & INSTALLATION. Disconnect
harness connector. Set actuator in LOCK position. Connect positive
lead of 12-volt power source to actuator terminal No. 3 (Blue/Red
wire) on Montero or terminal No. 1 (Blue/Red wire) on 3000GT. See
WIRING DIAGRAMS . Actuator should move to UNLOCK position when terminal
No. 1 (White/Black wire) on Montero or terminal No. 3 (Blue/Black
wire) on 3000GT is connected to ground.
2) With actuator set in UNLOCK position, connect positive
lead of 12-volt power source to actuator terminal No. 1 (White/Black
wire) on Montero or terminal No. 3 (Blue/Black wire) on 3000GT. See
WIRING DIAGRAMS . Actuator should move to LOCK position when terminal
No. 3 (Blue/Red wire) on Montero or terminal No. 1 (Blue/Red wire) o\
n
3000GT is connected to ground.
3) On 3000GT, check for continuity between actuator terminals
No. 2 (Brown wire) and No. 4 (Black wire). See WIRING DIAGRAMS.
Continuity should be present with actuator set in UNLOCK position.
Page 400 of 1501

Continuity should not be present with actuator set to LOCK position.
Left Rear Door (Montero)
1) Access and disconnect harness from left rear door lock
actuator. See DOOR LOCK ACTUATOR R & I under REMOVAL & INSTALLATION.
Set actuator in LOCK position. Connect positive lead of 12-volt power
source to actuator terminal No. 3 (Blue/Red wire). See WIRING DIAGRAMS
. Actuator should move to UNLOCK position when terminal No. 1
(Blue/Black wire) is connected to ground.
2) With actuator set in UNLOCK position, connect positive
lead of 12-volt power source to actuator terminal No. 1 (Blue/Black
wire). See WIRING DIAGRAMS . Actuator should move to LOCK position when
terminal No. 3 (Blue/Red wire) is connected to ground.
Right Rear Door (Montero)
1) Access and disconnect harness from right rear door lock
actuator. See DOOR LOCK ACTUATOR R & I under REMOVAL & INSTALLATION.
Set actuator in LOCK position. Connect positive lead of 12-volt power
source to actuator terminal No. 1 (Blue/Black wire). See
WIRING DIAGRAMS . Actuator should move to UNLOCK position when terminal
No. 3 (Blue/Red wire) is connected to ground.
2) With actuator set in UNLOCK position, connect positive
lead of 12-volt power source to actuator terminal No. 3 (Blue/Red
wire). See WIRING DIAGRAMS . Actuator should move to LOCK position when
terminal No. 1 (Blue/Black wire) is connected to ground.
DOOR LOCK POWER RELAY
1) Remove door lock relay. See COMPONENT LOCATIONS. Check for
continuity between relay terminals No. 1, 3 and 5, and terminals No.
4, 7 and 8. See RELAY TERMINAL IDENTIFICATION table. Continuity should
be present.
2) Apply positive battery voltage to relay terminal No. 7 and
ground to terminals No. 4 and 8. Check for continuity between relay
terminals No. 1 and 2, and terminals No. 2 and 3. See
RELAY TERMINAL IDENTIFICATION table. Continuity should be present.
Replace relay if continuity is not as specified.
RELAY TERMINAL IDENTIFICATION TABLE
\
\
\
\
\
\
Application & Harness
Terminal No. Wire Color
Montero
1 ........................................... Blue/Green
2 ............................................ Red/White
3 .......................................... Blue/Orange
4 ............................................ Black/Red
5 ................................................ Black
7 ............................................ Red/Black
8 ......................................... Black/Yellow
3000GT (Relays No. 1 & 2)
1 ........................................... Blue/Black
2 ............................................ Red/Black
3 ............................................. Blue/Red
4 .......................................... Brown/White
5 ................................................ Black
7 ............................................ Red/Black
8 ........... Brown/Blue (No. 1) Or Yellow/Black (No. 2)
\
\
\
\
\
\
DOOR LOCK CYLINDER SWITCH