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All switches are mounted to transfer case. See Fig. 9.
Switches use single harness lead and ground to transfer case. See 4WD
INDICATOR SWITCH CONTINUITY CHECK table. Ensure all appropriate
grounding straps are connected to vehicle body or frame.
4WD INDICATOR SWITCH CONTINUITY CHECK
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Switch Transfer Control Lever Position Specification
Center Differential Lock
Detection Switch .............. 4H ................. No Continuity
Detection Switch ............. 4HLc ................... Continuity
Center Differential Lock
Operation Detection Switch .. 4H .................. No Continuity
" ........................... 4HLc .................... Continuity
4WD Operation
Detection Switch .............. 2H ................. No Continuity
Detection Switch .............. 4H .................... Continuity
HI/LO Detection Switch ...... 4HLc .................... Continuity
" ............................. N .................. No Continuity
" ........................... 4LLc .................... Continuity
2WD/4WD
Detection Switch ............ 2H .................... Continuity
" ........................... 4H ................. No Continuity
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REAR DIFFERENTIAL CONTROL UNIT
Remove rear seat and remove rear differential control unit.
Do not disconnect control unit harness connector. Backprobe harness
connector. Check voltage between each individual terminal and ground
terminal No. 6 (Black wire). See Figs. 14 and 15. If after all tests
have been completed system is not operating properly, substitute rear
differential control unit with known good-unit and retest.
Fig. 14: Identifying Rear Differential Control Unit Connector
Courtesy of Mitsubishi Motor Sales of America.
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Fig. 15: Rear Differential Control Unit Pin Voltage Chart
Courtesy of Mitsubishi Motor Sales of America.
WHEEL SPEED SENSOR (WSS)
WSS Resistance Test
1) Before testing WSS resistance, ensure pole piece-to-WSS
tip is clean. Check WSS pole piece for damage. If pole piece is
damaged, replace WSS.
2) Disconnect WSS connector. Inspect WSS wiring harness for
broken and pinched wires. See WIRING DIAGRAMS. Repair harness as
necessary. If harness is okay, go to next step.
3) Using ohmmeter, check resistance across WSS terminals.
Resistance for front WSS should be 1170-1350 ohms. Resistance for rear
WSS should be 1300-1500 ohms. If resistance is as specified, go to
GROUND CIRCUIT TEST. If resistance is not as specified, replace WSS.
Ground Circuit Test
Disconnect WSS wiring harness connector. Check resistance
between each WSS terminal and WSS housing. Resistance should be more
than 100,000 ohms. If resistance is not as specified, replace WSS.
REMOVAL & INSTALLATION
ELECTRONIC CONTROL UNIT (ECU)
Removal & Installation
1) ECU is located behind right rear quarter panel trim. See
Fig. 16 . Disconnect negative battery cable. Remove quarter panel
mounti ng screws and trim clip.
2) Carefully remove quarter panel trim. Disconnect ECU wiring
harness connector. Remove ECU mounting bolts/nuts and ECU. To install,
reverse removal procedure.
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Fig. 16: Locating Electronic Control Unit (ECU)
Courtesy of Mitsubishi Motor Sales of America.
"G" SENSOR
CAUTION: DO NOT turn "G" sensor upside-down or lay unit on its side.
DO NOT drop "G" sensor. DO NOT disassemble unit. Replace "G"
sensor as an assembly.
Removal & Installation
Sensor is located under center console, near shifter. See
Fig. 10 . Remove center console assembly. Disconnect sensor wiring
harnes s connector. Remove sensor. To install, reverse removal
procedure. Tighten bolts to specification. See TORQUE SPECIFICATIONS.
HYDRAULIC UNIT
Removal
Remove brakelines from hydraulic unit. Remove ABS relay box
cover. See Fig. 3. Disconnect ground wire and wiring harness
connectors from hydraulic unit. Remove hydraulic unit retaining nuts.
Carefully remove hydraulic unit.
Installation
To install, reverse removal procedure. Install hydraulic unit
brakelines. Ensure brakelines are installed in correct location. See
Fig. 17. Bleed brake system. See BLEEDING BRAKE SYSTEM.
Page 148 of 1501
Fig. 17: Identifying Hydraulic Unit Brakeline Connections
Courtesy of Mitsubishi Motor Sales of America.
WHEEL SPEED SENSOR (WSS)
Page 149 of 1501
Removal & Installation
Disconnect WSS connector. Remove WSS bolts. Remove WSS from
vehicle. To install, reverse removal procedure. Sensors are not
interchangeable. Adjust wheel WSS-to-rotor gap. See WHEEL SPEED SENSOR
(WSS) under ADJUSTMENTS. To complete installation, reverse removal
procedure. Tighten WSS bolts to specification. See
TORQUE SPECIFICATIONS .
WHEEL SENSOR ROTOR
Removal & Installation
Remove brake disc. Remove disc assembly. Remove wheel
bearings. Remove axle hub. Remove bolts attaching sensor rotor to hub
assembly. To install, reverse removal procedure.
OVERHAUL
HYDRAULIC UNIT
DO NOT attempt to overhaul or disassemble hydraulic unit. If
hydraulic unit is defective, replace entire assembly.
TORQUE SPECIFICATIONS
TORQUE SPECIFICATIONS \
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Application INCH Lbs. (N.m)\
"G" Sensor Mounting Bolt ................................. 80 (9.0)\
Wheel Speed Sensor (WSS) Bolt .................... 84-120 (9.5-14.6\
)
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WIRING DIAGRAMS
Page 150 of 1501
Fig. 18: Anti-Lock Brake System (ABS) Wiring Diagram (1997 Montero)\
Page 151 of 1501
Fig. 19: Anti-Lock Brake System (ABS) Wiring Diagram (1998 Montero)\
Page 152 of 1501

AUTO TRANS DIAGNOSIS - R4AW3 & V4AW3
1998 Mitsubishi Montero
1997-98 AUTOMATIC TRANSMISSIONS
Mitsubishi R4AW3 & V4AW3 Electronic Controls
Montero, Montero Sport
APPLICATION
TRANSMISSION APPLICATION \
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Vehicle Transmission Model
Montero Sport 2WD ............................................ R4AW3
Montero & Montero Sport 4WD .................................. V4AW3
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CAUTION: Vehicle is equipped with Supplemental Restraint System (SRS).
When servicing vehicle, use care to avoid accidental air bag
deployment. SRS-related components are located in steering
column, center console, instrument panel and lower panel on
instrument panel. DO NOT use electrical test equipment on
these circuits. If necessary, deactivate SRS before servicing
components. See AIR BAG SERVICING article in APPLICATIONS &
IDENTIFICATION.
DESCRIPTION
Automatic transmission is a 4-speed electronically controlled
transmission. Solenoids that control shift changes are located in
valve body. Solenoids are controlled by a Transmission Control Module
(TCM). TCM receives information from various input devices and uses
this information to control shift solenoids for transmission shifting
and lock-up solenoid for torque converter lock-up.
An Overdrive (OD) switch is mounted on the shift lever. When
OD switch is depressed to ON position, transmission will shift into
4th gear when shift lever is in "D" position, and OD OFF light on
instrument panel will go off. When OD switch is released to OFF
position, transmission will shift into 3rd gear, and OD OFF light on
instrument panel will illuminate.
A pattern select switch is located near shift lever on center
console. Pattern select switch contains a NORMAL and a HOLD operating
position. When pattern select switch is depressed (HOLD position) with\
shift lever in Drive position, transmission starts in 2nd gear.
Upshifts and downshifts will occur at a higher vehicle speed than with
switch in NORMAL position. See MITSUBISHI R4AW3 & V4AW3 OVERHAUL
article. Indicator light on instrument panel indicates pattern select
switch is in HOLD position.
Transmission is equipped with a shift lock and key interlock
system. Shift lock system prevents shift lever from being moved from
Park unless brake pedal is depressed. Key interlock system prevents
ignition key from being moved from ACC to LOCK position on ignition
switch unless shift lever is in Park. See MITSUBISHI SHIFT LOCK
SYSTEMS article.
OPERATION
TCM
TCM receives information from various input devices and uses