Mitsubishi Montero (2002-2004). Manual — part 868

AUTOMATIC TRANSMISSION DIAGNOSIS

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AUTOMATIC TRANSMISSION DIAGNOSIS

23Ab-13

8

Use scan tool
MB991502 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.23Ac-160

)

33

Second
solenoid valve
system
(

P.23Ac-171

)

44

4th gear
incorrect ratio
(

P.23Ac-215

)

45

5th gear
incorrect ratio
(

P.23Ac-215

)

9

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

Monitor data list
No. 22 and No.
23 with scan tool
MB991502.
(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.23Ac-47

)

23

Output shaft
speed sensor
system
(

P.23Ac-65

)

46

Reverse gear
incorrect ratio
(

P.23Ac-215

)

STEP CONDITION

BEFORE TEST/
OPERATION

TEST/
OPERATION

STANDARD

INSPECTION
ITEM

DTC

INSPECTION
PROCEDURE
PAGE

AUTOMATIC TRANSMISSION DIAGNOSIS

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AUTOMATIC TRANSMISSION DIAGNOSIS

23Ab-14

TORQUE CONVERTER STALL TEST

M1231103500100

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 MB991502 (MUT-II).

2. Chock both front wheels.
3. Connect a tachometer.
4. Apply the parking and service brakes fully.
5. Start the engine.
6. Move the selector lever to the "D" position. Fully depress the

accelerator pedal and read the maximum engine speed.

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.

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 DIAGNOSIS

23Ab-15

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

M1231103800101

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)

CAUTION

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

AUTOMATIC TRANSMISSION DIAGNOSIS

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AUTOMATIC TRANSMISSION DIAGNOSIS

23Ab-16

STANDARD HYDRAULIC PRESSURE TEST

NOTE: If the torque converter clutch pressure is measured, the engine speed should be 1,500 r/min or less.

MEASUREMENT
CONDITION

STANDARD HYDRAULIC PRESSURE MPa (psi)

TRANS-
MISSION
RANGE

SHIFT
POSITION

ENGINE
SPEED
(r/min)

UNDERDRIVE
CLUTCH
PRESSURE
[UC]

REVERSE
CLUTCH
PRESSURE
[RC]

OVERDRIVE
CLUTCH
PRESSURE
[OC]

DIRECT
CLUTCH
PRESSURE
[DC]

LOW-
REVERSE
BRAKE
PRESSURE
[LB]

SECOND
BRAKE
PRESSURE
[2B]

REDUC-
TION
BRAKE
PRESSURE
[RB]

TORQUE
CONVER-
TER
CLUTCH
PRESSURE
[TR]

P

−

2,500

−

−

−

−

0.26

−

0.34
(38

−

49)

−

1.01

−

1.05
(147

−

152)

0.22

−

0.36 (32
− 52)

R

Reverse

2,500

−

1.27

−

1.77
(185

−

256)

−

−

1.27

−

1.77
(185

−

256)

−

1.27

−

1.77
(185

−

256)

0.65

−

0.85 (94
− 123)

N

−

2,500

−

−

−

−

0.26

−

0.34
(38

−

49)

−

0.26

−

0.34
(38

−

49)

0.22

−

0.36 (32
− 52)

Sport
mode

1st
gear

2,500

1.01

−

1.05 (147
− 152)

−

−

−

1.01

−

1.05
(147

−

152)

−

1.01

−

1.05
(147

−

152)

0.65

−

0.85 (94
− 123)

2nd
gear

2,500

1.01

−

1.05 (147
− 152)

−

−

−

−

1.01

−

1.05 (147
− 152)

1.01

−

1.05
(147

−

152)

0.65

−

0.85 (94
− 123)

3rd
gear

2,500

0.78

−

0.88 (113
− 28)

−

0.78

−

0.88 (113
− 128)

−

−

−

0.78

−

0.88
(113

−

128)

0.65

−

0.85 (94
− 123)

4th
gear

2,500

0.78

−

0.88 (113
− 28)

−

0.78

−

0.88 (113
− 128)

0.78

−

0.88 (113
− 128)

−

−

−

−

5th
gear

2,500

−

−

0.78

−

0.88 (113
− 128)

0.78

−

0.88 (113
− 128)

−

0.78

−

0.88 (113
− 128)

−

−