Mitsubishi Montero (2004+). Manual — part 862

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-23

8

Use scan tool
MB991958
(MUT-III sub
assembly) to
stop the
INVECS-II
function.
Transmission
range: D (on a
flat and straight
road)

(1) Select to the
sport mode while
driving at 60
km/h (37 mph) in
5th gear, shift
down to 4th gear.
(2) While driving
at 40 km/h (37
mph) in 4th gear,
down shift to 3
range.
(3) While driving
at 20 km/h (25
mph) in 3rd gear,
down shift to 2nd
gear.
(4) While driving
at 20 km/h (12
mph) in 2nd
gear, down shift
to 1st gear.

Data list No.63
(1) 5th

→ 4th

(2) 4th

→ 3rd

(3) 3rd

→ 2nd

(4) 2nd

→ 1st

Does not shift
from 1 to 2 or 2
to 1

31

Low-reverse
solenoid valve
system
(

P.23A-177

)

33

Second solenoid
valve system
(

P.23A-203

)

41

1st gear incorrect
ratio (

P.23A-252

)

42

2nd gear
incorrect ratio
(

P.23A-252

)

Does not shift
from 2 to 3 or 3
to 2

33

Second solenoid
valve system
(

P.23A-203

)

34

Overdrive
solenoid valve
system
(

P.23A-215

)

42

2nd gear
incorrect ratio
(

P.23A-252

)

43

3rd gear incorrect
ratio (

P.23A-252

)

Does not shift
from 3 to 4 or 4
to 3

31

Low-reverse
solenoid valve
system
(

P.23A-177

)

35

Reduction
solenoid valve
system
(

P.23A-227

)

43

3rd gear incorrect
ratio (

P.23A-252

)

44

4th gear incorrect
ratio (

P.23A-252

)

STEP CONDITION

BEFORE TEST/
OPERATION

TEST/
OPERATION

STANDARD

INSPECTION
ITEM

DTC

INSPECTION
PROCEDURE
PAGE

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-24

8

Use scan tool
MB991958
(MUT-III sub
assembly) to
stop the
INVECS-II
function.
Transmission
range: D (on a
flat and straight
road)

(1) Select to the
sport mode while
driving at 60
km/h (37 mph) in
5th gear, shift
down to 4th gear.
(2) While driving
at 40 km/h (37
mph) in 4th gear,
down shift to 3
range.
(3) While driving
at 20 km/h (25
mph) in 3rd gear,
down shift to 2nd
gear.
(4) While driving
at 20 km/h (12
mph) in 2nd
gear, down shift
to 1st gear.

Data list No.63
(1) 5th

→ 4th

(2) 4th

→ 3rd

(3) 3rd

→ 2nd

(4) 2nd

→ 1st

Does not shift
from 4 to 5 or 5
to 4

32

Underdrive
solenoid valve
system
(

P.23A-191

)

33

Second solenoid
valve system
(

P.23A-203

)

44

4th gear incorrect
ratio (

P.23A-252

)

45

5th gear incorrect
ratio (

P.23A-252

)

9

Transmission
range: N (on a
flat and straight
road)

Monitor data list
No.22 and No.23
with scan tool
MB991958
(MUT-III sub
assembly).
(1)Move selector
lever to R range,
drive at constant
speed of 10 km/h
(6.2 mph).

The ratio
between data list
No.22 and No.23
should be the
same as the gear
ratio when
reversing.

Does not
match

22

Input shaft speed
sensor system
(

P.23A-71

)

23

Output shaft
speed sensor
system
(

P.23A-91

)

46

Reverse gear
incorrect ratio
(

P.23A-252

)

STEP CONDITION

BEFORE TEST/
OPERATION

TEST/
OPERATION

STANDARD

INSPECTION
ITEM

DTC

INSPECTION
PROCEDURE
PAGE

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-25

TORQUE CONVERTER STALL TEST

M1231103500111

This test measures the maximum engine speed when the
selector lever is in the "D" or "R" position and the torque con-
verter stalls. This tests the operation of the torque converter
(stator and one-way clutch operation) as well as the holding
performance of the clutches and brakes in the transmission.

WARNING

Do not let anyone stand in front of or behind the vehi-
cle while this test is performed.

1. Check the transmission fluid level and temperature. Check

the engine coolant temperature.

• Transmission fluid level: At the "HOT" mark on the dipstick

• Transmission fluid temperature: 70 − 80°C (158 − 176°F)

• Engine coolant temperature: 80 − 100°C (176 − 212°F)

NOTE: Measures transmission fluid temperature with scan
tool MB991958 (MUT-III sub assembly).

2. Chock both front wheels.
3. Connect a tachometer.
4. Apply the parking and service brakes fully.
5. Start the engine.

CAUTION

• The throttle should not be fully open for any more than

five seconds.

• If you repeat the stall test when the transmission fluid

temperature is greater than 80

°C (176°F) move the

selector lever to the "N" position and let the engine run
at approximately 1,000 r/min for at least one minute.
Wait until the transmission fluid temperature returns to
80

°C (176°F) or less.

6. Move the selector lever to the "D" position. Fully depress the

accelerator pedal and read the maximum engine speed.

Standard value: Stall speed: 2,200

− 2,700 r/min

7. Move the selector lever to the "R" position. Fully depress the

accelerator pedal and read the maximum engine speed.

Standard value: Stall speed: 2,200

− 2,700 r/min

TORQUE CONVERTER STALL TEST JUDGMENT
RESULTS

1. Stall speed is too high in both "D" and "R" ranges

• Malfunction of the torque converter (Slippage on the splines

of the torque converter and the input shaft)

• Low line pressure

• Low-reverse brake slippage and malfunction of the one-way

clutch

2. Stall speed is too high in "D" range only

• Underdrive clutch slippage

3. Stall speed is too high in "R" range only

• Reverse clutch slippage

• Low-reverse brake slippage

• Reduction brake slippage

AC204712 AB

LOW-REVERSE
BRAKE

ONE WAY CLUTCH

REVERSE
CLUTCH

UNDERDRIVE
CLUTCH

REDUCTION
BRAKE

TORQUE
CONVERTER

AUTOMATIC TRANSMISSION DIAGNOSIS

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AUTOMATIC TRANSMISSION

23A-26

4. Stall speed is too low in both "D" and "R" ranges

• Malfunction of the torque converter (Slippage of the

one-way clutch)

• Insufficient engine output

HYDRAULIC PRESSURE TESTS

M1231103800112

Required Special Tool:

• MB998330: Oil Pressure Gauge

• MB998332: Adapter

• MB998900: Adapter

CAUTION

The transmission fluid temperature should be between 70
− 80°C (158 − 176°F) during the test.

1. Check the transmission fluid level and temperature. Check

engine coolant temperature.

• Transmission fluid level: "HOT" mark on the dipstick

• Transmission fluid temperature: 70 − 80°C (158 − 176°F)

• Engine coolant temperature: 80 − 100°C (176 − 212°F)

2. Raise the vehicle so that the wheels are free to turn.
3. Connect the special tools (3.0 MPa (427 psi) oil pressure

gauge [MD998330] and adapters [MD998332, MD998900])
to each pressure discharge port.
NOTE:

.

•

UC: Underdrive clutch pressure port

•

RC: Reverse clutch pressure port

•

OC: Overdrive clutch pressure port

•

DC: Direct clutch pressure port

•

LB: Low-reverse brake pressure port

•

2B: Second brake pressure port

•

RB: Reduction brake pressure port

•

TA: Torque converter apply pressure port

•

TR: Torque converter release pressure port

4. Restart the engine.
5. Check that there are no leaks around the special tool port

adaptors.

6. Measure the hydraulic pressure at each port under the

conditions given in the standard hydraulic pressure table,
and check that the measured values are within the standard
value ranges.

7. If the pressure is not within the standard value, stop the

engine and refer to the hydraulic pressure test diagnosis
table.

8. Remove the O-ring from the port plug and replace it.
9. Remove the special tool, and install the plugs to the

hydraulic pressure ports.

10.Start the engine and check that there are no leaks around

the plugs.

AC101188AB

MD998900

MD998330

OIL PAN

AC101189AB

MD998900

MD998330

TRANSMISSION CONTROL
CABLE

AC101190AC

MD998332

MD998330

OIL COOLER TUBE CONNECTION