Mitsubishi Montero Sport (2004+). Manual - part 613

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-17

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.

AK303629AB

MB991911

MB991827

MB991824 

16-PIN

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-18

FAIL-SAFE/BACKUP FUNCTION

M1231101100128

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.

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 transaxle will only operate 
in 3rd and reverse gears until the system is 
repaired.

Underdrive solenoid valve
Second solenoid valve
Overdrive solenoid valve
Torque converter clutch 
solenoid valve
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 transaxle will only operate 
in 3rd and reverse gears until the system is 
repaired.

2nd
3rd
4th
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.

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-19

ROAD TEST

M1231100800157

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-319

)

2

Ignition switch: 
ON
Engine: Stopped
Transmission 
range: P

Transmission 
range
(1) P, (2) R, (3) N, 
(4) D, (5) 3, (6) 2, 
(7) L

Data list No.61
(1) P, (2) R, (3) N, 
(4) D, (5) 3, (6) 2, 
(7) L

Transmission 
range switch

27, 
28

Transmission 
range switch 
system 
(

P.23A-123

 , 

P.23A-181

)

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

Data list No.11
(1) 535 

− 735 mV

(2) Gradually rises 
from (1)
(3) 4,500 

− 5,500 

mV

TP sensor

11, 
12, 
14

Group 13A, 
Diagnostic 
Trouble Code 
Procedures 

− 

DTCs P0121, 
P0122, 0123: 
Throttle 
Position Sensor 
System 
(

P.13A-137

, 

P.13A-148

,  

P.13A-157

).

Brake pedal
(1) Depressed
(2) Released

Data list No. 26
(1) ON
(2) OFF

Stoplight switch 26

Stoplight switch 
system 
(

P.23A-113

)

Transfer position 
<V4A51>
(1) Other than 4L
(2) 4L 

Data list No.75
(1) OFF
(2) ON

Transfer low 
detection switch 
<V4A51>

−

Transfer low 
detection switch 
<V4A51> 
(

P.23A-398

) 

3

Ignition switch: 
ST
Engine: Stopped

Cranking test with 
lever in P or N 
range

Cranking should 
be possible.

Cranking

−

Engine does not 
crank 
(

P.23A-343

).

4

Engine warmed

Drive for 15 
minutes or more 
so that the 
transmission fluid 
temperature 
becomes 70 

− 

80

°C. (158 − 

176

°F)

Data list No.15
Gradually rises to 
70 

− 80°C (158 − 

176

°F)

Transmission 
fluid 
temperature 
sensor

15, 
16

Transmission 
fluid 
temperature 
sensor system 
(

P.23A-42

, 

P.23A-59

)

5

Engine: Idling
Transmission 
range: N

Brake pedal 
(Retest)
(1) Depressed
(2) Released

Data list No.26
(1) ON
(2) OFF

Stoplight switch 26

Stoplight switch 
system 
(

P.23A-113

)

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-20

5

Engine: Idling
Transmission 
range: N

A/C switch
(1) ON
(2) OFF

Data list No.65
(1) ON
(2) OFF

Dual pressure 
switch

−

Vehicle shifts 
differently with 
A/C engaged 
(

P.23A-376

).

Accelerator pedal
(1) Fully closed
(2) Depressed

Data list No.21
(1) Engine 
tachometer and 
the scan tool 
MB991958 
(MUT-III sub 
assembly) show 
the same engine 
speed.
(2) Gradually rises 
from (1).

Crankshaft 
position sensor

21

Group 13A, 
Diagnostic 
Trouble Code 
Procedures 

− 

DTC P0335: 
Crank shaft 
Position Sensor 
System 
(

P.13A-452

).

Transmission 
range
(1) N 

→ D

(2) N 

→ R

Should be no 
abnormal shift 
shocks.
Time delay when 
engaging should 
be within 2 
seconds.

Malfunction 
when starting

−

Engine stalls 
when moving 
selector lever 
from N to D or N 
to R 
(

P.23A-352

)

−

Shift shock 
when shifting 
from N to D and 
long delay 
(

P.23A-353

)

−

Shift shock 
when shifting 
from N to R and 
long delay 
(

P.23A-357

)

−

Shift shock 
when shifting 
from N to D, N 
to R and long 
delay 
(

P.23A-360

)

Does not move

−

Does not move 
forward 
(

P.23A-345

)

−

Does not move 
backward 
(

P.23A-348

)

−

Does not move 
(forward or 
backward) 
(

P.23A-350

)

STEP CONDITION 

BEFORE TEST/
OPERATION

TEST/
OPERATION

STANDARD

INSPECTION 
ITEM

DTC INSPECTION 

PROCEDURE 
PAGE