Mitsubishi Montero Sport (2004+). Manual - part 700

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-365

STEP 1. Using scan tool MB991958, check data list item 23: 
Output Shaft Speed Sensor.

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) Start the engine.
(3) Set scan tool MB991958 to data reading mode.

• Item 23: Output Shaft Speed Sensor.

• When driving at constant speed of 50 km/h (31 

mph), the display should be "1,400 

− 1,700 r/min" 

(Gear range: 3rd gear).

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : Go to Step 2.
NO :  Refer to 

P.23A-91

, DTC 23: Output shaft speed 

sensor system.

STEP 2. Using scan tool MB991958, check data list item 11: 
TP Sensor.

(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.

(3) Set scan tool MB991958 to data reading mode.

• Item 11: TP Sensor.

• With the throttle valve in the idle position, voltage 

should measure between 535 and 735 mV.

• With the throttle valve in the full-open position, volt-

age should measure between 4,500 and 5,500 mV.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage between 535 and 735mV at idle, 

and between 4,500 and 5,500 mV in the full-open 
position? 
YES : Go to Step 3.
NO :  Check the TP sensor. Refer to GROUP 13A, 

On-vehicle Service 

P.13A-890

. Then check the 

malfunction.

AK303629AB

MB991911

MB991827

MB991824 

16-PIN

AK303629AB

MB991911

MB991827

MB991824 

16-PIN

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-366

STEP 3. Using scan tool MB991958, check data list.

(1) Connect scan tool MB991958 to the data link connector.
(2) Start the engine.

(3) Set scan tool MB991958 to data reading mode for following 

items.

a. Item 31: Low-Reverse Solenoid Valve Duty Percent
b. Item 32: Underdrive Solenoid Valve Duty Percent

c. Item 33: Second Solenoid Valve Duty Percent

d. Item 34: Overdrive Solenoid Valve Duty Percent

• Check that the values shown below are displayed 

when each data list item is entered.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Are the solenoid valves operating properly?

YES : Go to Step 4.
NO :  Go to Step 6.

STEP 4. Adjust the line pressure.

Adjust the line pressure. Refer to 

P.23A-39

, Line Pressure 

Adjustment. Then check the symptom.
Q: Is the symptom eliminated?

YES : The procedure is complete.
NO :  Go to Step 5.

AK303629AB

MB991911

MB991827

MB991824 

16-PIN

DRIVING CONDITION

DATA LIST ITEM
31

32

33

34

Driving at constant speed of 10 km/h (6.2 mph) in 
1st gear

0%

0%

100%

100%

Driving at constant speed of 30 km/h (19 mph) in 
2nd gear

100%

0%

0%

100%

Driving at constant speed of 50 km/h (31 mph) in 
3rd gear

100%

0%

100%

0%

Driving at constant speed of 50 km/h (31 mph) in 
4th gear

100%

100%

0%

0%

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-367

STEP 5. Disassemble and clean the valve body.

Check the O-ring installation bolts for looseness and the valve 
body for damage. Repair or replace the faulty parts. Refer to 
GROUP 23B, Valve Body 

P.23B-67

.

Replace the valve body assembly if the damages are thought 
to be irreparable. Then check the symptom.
Q: Is the symptom eliminated?

YES : The procedure is complete.
NO :  Go to Step 7.

STEP 6. Replace each solenoid valve.

Replace the faulty solenoid valve with a new one.
Q: Is the symptom eliminated?

YES : The procedure is complete.
NO :  Go to Step 7.

STEP 7. Replace the PCM.
Q: Is the symptom eliminated?

YES : The procedure is complete.
NO :  Start over at Step 1.

INSPECTION PROCEDURE 11: Early or Late Shifting in Some Gears

.

COMMENT
If some of the shift points are early or late when driv-
ing, the cause is probably a malfunction of the valve 
body, or it is due to the characteristics of the 
INVECS-II system but is not an abnormality.

.

TROUBLESHOOTING HINTS (The most likely 
causes for this case:)

• Malfunction of the valve body

• Malfunction of the PCM

DIAGNOSIS

Required Special Tool:

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

• MB991824: V.C.I.

• MB991827: MUT-III USB Cable

• MB991911: MUT-III Main Harness B

AC004272

VALVE BODY ASSEMBLY

AB

AC004272

TORQUE CONVERTER
CLUTCH SOLENOID VALVE

AD

UNDERDRIVE
SOLENOID VALVE

LOW-REVERSE
SOLENOID
VALVE

OVERDRIVE
SOLENOID
VALVE

SECOND
SOLENOID
VALVE

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-368

STEP 1. Using scan tool MB991958, check actuator test 
item 14: INVECS-II Cancel Command.

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) Start the engine.
(3) Set scan tool MB991958 to actuator test mode.

• Item14: INVECS-II Cancel Command.

• Drive the vehicle and confirm the gear shifting corre-

spond to the standard shift line of the shift pattern 
diagram. Refer to 

P.23A-3

.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Does the gear shifting correspond to the standard shift 

line of the shift pattern diagram?
YES : The symptom is due to characteristics of the 

INVECS-II system, but is not abnormal.

NO :  Go to Step 2.

STEP 2. Check the shift points.
Q: Are the shift points early or late only when transmission 

fluid is -29

°C (84°F) or less (early), or 125°C (257°F) or 

more (late)?
YES : The symptom is due to characteristics of the 

INVECS-II system, but is not abnormal.

NO :  Go to Step 3.

STEP 3. Disassemble and clean the valve body.

Check the O-ring installation bolts for looseness and the valve 
body for damage. Repair or replace the faulty parts. Refer to 
GROUP 23B, Valve Body 

P.23B-67

.

Replace the valve body assembly if the damages are thought 
to be irreparable. Then check the symptom.
Q: Is the symptom eliminated?

YES : The procedure is complete.
NO :  Go to Step 4.

AK303629AB

MB991911

MB991827

MB991824 

16-PIN

AC004272

VALVE BODY ASSEMBLY

AB