Mitsubishi Montero (2004+). Manual — part 860

AUTOMATIC TRANSMISSION DIAGNOSIS

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AUTOMATIC TRANSMISSION

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HOW TO PERFORM ACTUATOR TEST

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: MUT-III USB Cable

• MB991911: MUT-III Main Harness B

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Select "Interactive Diagnosis" from the start-up screen.
4. Select "System select."
5. Choose "ELC-A/T" from the "POWER TRAIN" tab.
6. Select "MITSUBISHI."
7. Select "Actuator Test."
8. Choose an appropriate item and select the "OK" button.

FAIL-SAFE/BACKUP FUNCTION

M1231101100117

When a malfunction of a main sensor or actuator is
detected by the PCM, the transmission is controlled
by pre-set control logic to maintain safe conditions
for driving.

The following table shows how the fail-safe/backup
function affects vehicle driveability and operation.

AC307591 AC

MB991911

MB991824

MB991827

AC307591

DATA LINK

CONNECTOR

AUTOMATIC TRANSMISSION DIAGNOSIS

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AUTOMATIC TRANSMISSION

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MALFUNCTIONING ITEM JUDGMENT CONDITION

CONTROL DEFAULT DURING MALFUNCTION

Input shaft
speed
sensor

If no output pulse from the
input shaft speed sensor is
detected for one second or
more when the vehicle
speed is 30 km/h (19 mph)
or greater.

The diagnostic trouble code is recorded when the
malfunction occurs once during 4 monitoring
periods in one drive cycle. When the judgment
condition is met, the transmission holds 3rd gear
or 2nd gear, depending on speed and "N" range
light flashes as a fail-safe.

Output shaft
speed
sensor

Output from the output
shaft speed sensor is
continuously 50% or less of
the output from the vehicle
speed sensor one second
or more when the vehicle
speed is 30 km/h (19 mph)
or more.

The diagnostic trouble code is recorded when the
malfunction occurs once during 4 monitoring
periods in one drive cycle. When the judgment
condition is met, the transmission holds 3rd gear
or 2nd gear, depending on speed and "N" range
light flashes as a fail-safe.

Low-reverse
solenoid
valve

Solenoid valve resistance
is below 2.7 ohms for 0.32
seconds.

The diagnostic trouble code is recorded when the
malfunction occurs during 4 monitoring periods in
one drive cycle. When the judgment condition is
met, the A/T control relay is turned off and "N"
range light flashes. The transmission will only
operate in 3rd and reverse gears until the system
is repaired.

Underdrive
solenoid
valve
Second
solenoid
valve
Overdrive
solenoid
valve
Reduction
solenoid
valve
Torque
converter
clutch
solenoid
valve

AUTOMATIC TRANSMISSION DIAGNOSIS

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AUTOMATIC TRANSMISSION

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Incomplete
shifting

1st

The gear ratio value from
the output shaft speed
sensor is not the same as
the output from the input
shaft speed sensor for one
second after shifting has
been completed.

The diagnostic trouble code is recorded when the
malfunction occurs during 4 monitoring periods in
one drive cycle. When the judgment condition is
met, the A/T control relay is turned off and "N"
range light flashes. The transmission will only
operate in 3rd and reverse gears until the system
is repaired.

2nd
3rd
4th
5th
Reverse

A/T control
relay

A/T control relay voltage is
less than seven volts for
0.1 second after the ignition
switch is turned "ON."

The A/T control relay is switched off. The
transmission will only operate in 3rd and Reverse
gears until the system is repaired.

Malfunction
in the PCM

Malfunction has occurred in
the PCM.

The A/T control relay is switched off. The
transmission will only operate in 3rd and Reverse
gears until the system is repaired.

MALFUNCTIONING ITEM JUDGMENT CONDITION

CONTROL DEFAULT DURING MALFUNCTION

AUTOMATIC TRANSMISSION DIAGNOSIS

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AUTOMATIC TRANSMISSION

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ROAD TEST

M1231100800146

Check using the following procedures

STEP CONDITION

BEFORE TEST/
OPERATION

TEST/
OPERATION

STANDARD

INSPECTION
ITEM

DTC

INSPECTION
PROCEDURE
PAGE

1

Ignition switch:
OFF

Ignition switch
(1) ON

Data list No.54

(1) Control

Relay Voltage
[V]

A/T Control
relay output
voltage

54

A/T Control relay
system
(

P.23A-277

)

2

Ignition switch:
ON
Engine: Stopped
Transmission
range: P

Transmission
range
(1) P, (2) R, (3)
N, (4) D

Data list No.61
(1) P, (2) R, (3)
N, (4) D

Transmission
range switch

27, 28

Transmission
range switch
system
(

P.23A-121

,

P.23A-150

)

Transmission
range
(1) D (1st gear)
(2) Select the
sport mode (1st
gear)
(3) Upshift and
hold the selector
lever in that
position (2nd
gear)
(4) Downshift
and hold the
selector lever in
that position (1st
gear)

Data list No.67
(1) OFF, (2) ON,
(3) ON, (4) ON
Data list No.68
(1) OFF, (2) OFF,
(3) ON, (4) OFF
Data list No.69
(1) OFF, (2) OFF,
(3) OFF, (4) ON

Select switch
Shift switch

-

Shift switch
assembly system
(

P.23A-355

)

Shift indicator
light
(1) "D" and "1"
illuminates
(2) Only "1"
illuminates
(3) Only "2"
illuminates
(4) Only "1"
illuminates

Accelerator
pedal
(1) Fully closed
(2) Depressed
(3) Fully open

Data list No.11
(1) 200

− 800 mV

(2) Gradually
rises from (1)
(3) 3,800

− 4,900

mV

Throttle
position sensor

−

Group 13A,
Diagnostic
Trouble Code
Procedures

−

DTCs P0122,
0123: Throttle
Position Sensor
System
(

P.13A-138

,

P.13A-147

).