automatic transmission MITSUBISHI 380 2005 Owner's Guide

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-18
FAIL-SAFE/BACKUP FUNCTIONM1231008300234
When a malfunction of a main sensor or actuator is
detected by the A/T-ECU, the transmission is con-
trolled by pre-set control logic to maintain safe condi-
tions for driving.The following table shows how the fail-safe/backup
function affects vehicle driveability and operation.
MALFUNCTIONING ITEM JUDGEMENT
CONDITIONCONTROL 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 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, as a fail-safe.
Output shaft speed sensor The output signal
from the output shaft
speed sensor is not
present for one
second or more
while the vehicle is
driven.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 transmission holds 3rd gear or 2nd gear,
depending on speed, 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 5 monitoring periods in
one drive cycle. When the judgment condition is
met, the A/T control relay is turned off. 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 (RED) solenoid valve
Damper control clutch (DCC)
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 5 monitoring periods in
one drive cycle. When the judgment condition is
met, the A/T control relay is turned off. 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 A/T-ECU Malfunction has
occurred in the
A/T-ECU.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
AUTOMATIC TRANSMISSION23A-19
ROAD TESTM1231007800407
Check using the following procedures.
STEP CONDITION
BEFORE
TEST/OPERATIONTEST/OPERATION STANDARD INSPECTION
ITEMINSPECTION
PROCEDURE
PA G E
1 Ignition switch:
(LOCK) OFFIgnition switch
(1) ONData list No.8
(1) Control Relay
Voltage [V]A/T Control
relay
output
voltageA/T Control
relay system
(P.23A-207).
2 Ignition switch:
ON
Engine: Stopped
Transmission
range: PTransmission range
(1) P, (2) R, (3) N, (4)
DData list No.34
(1) P, (2) R, (3) N, (4)
DTransmissi
on range
switchTransmission
range switch
system
(P.23A-97,
P.23A-119).
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.27
(1) OFF, (2) ON, (3)
ON, (4) ON
Data list No.28
(1) OFF, (2) OFF, (3)
ON, (4) OFF
Data list No.29
(1) OFF, (2) OFF, (3)
OFF, (4) ONSelect
switch and
Shift switchShift switch
assembly
system
(P.23A-252).
Brake pedal
(1) Depressed
(2) ReleasedData list No.19
(1) ON
(2) OFFSto pl amp
switchSt o pla mp
switch system
(P.23A-89).
3 Ignition switch:
ST
Engine: StoppedCranking test with
lever in P or N rangeCranking should be
possibleCranking Engine does
not crank
(P.23A-218).
4 Engine warming
upDrive for 15 minutes
or more so that the
transmission fluid
temperature
becomes 70
90CData list No.7
Gradually rises to 70
90CTransmissi
on fluid
temperatur
e sensorTransmission
fluid
temperature
sensor system
(P.23A-36,
P.23A-47).
5 Engine: Idling
Transmission
range: NBrake pedal (Retest)
(1) Depressed
(2) ReleasedData list No.19
(1) ON
(2) OFFSto pl amp
switchSt o pla mp
switch system
(P.23A-89).
Transmission range
(1) N
D
(2) N
RShould be no
abnormal shift
shocks
Time delay when
engaging should be
within 2 secondsMalfunction
when
startingEngine stalls
when moving
selector lever
from N to D or
N to R
(P.23A-227).

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-20
Shift shock
when shifting
from N to D and
long delay
(P.23A-229).
Shift shock
when shifting
from N to R and
long delay
(P.23A-232).
Shift shock
when shifting
from N to D, N
to R and long
delay
(P.23A-235).
Does not
moveDoes not move
forward
(P.23A-220).
Does not move
in reverse
(P.23A-223).
Does not move
(forward or in
reverse)
(P.23A-226).
6 Transmission
range: N (on a
flat and straight
road)Gear range and
vehicle speed (Each
condition should be
maintained for 10
seconds or more).
(1) Idling in 1st gear
(Vehicle stopped)
(2) Driving at
constant speed of 10
km/h in 1st gear
(3) Driving at
constant speed of 30
km/h in 2nd gear
(4) Driving at
constant speed of 50
km/h in 3rd gear
(5) Driving at
constant speed of 70
km/h in 4th gear
(6) Driving at
constant speed of 70
km/h in 5th gearData list No.11
(2) 1st, (3) 2nd, (4)
3rd, (5) 4th, (6) 5thShift
position-
STEP CONDITION
BEFORE
TEST/OPERATIONTEST/OPERATION STANDARD INSPECTION
ITEMINSPECTION
PROCEDURE
PA G E

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-21
Data list No.12
(2) 100%, (3) 100%,
(4) 100%, (6) 100%Low-revers
e solenoid
valve duty
%Low-reverse
solenoid valve
system
(P.23A-133).
Data list No.13
(2) 0%, (3) 0%, (4)
0%, (6) 100%Underdrive
solenoid
valve duty
%Underdrive
solenoid valve
system
(P.23A-144).
Data list No.14
(2)100%, (3) 0%, (4)
0%, (6) 0%Second
solenoid
valve duty
%Second
solenoid valve
system
(P.23A-154).
Data list No.15
(2) 100%, (3) 100%,
(4) 0%, (6) 0%Overdrive
solenoid
valve duty
%Overdrive
solenoid valve
system
(P.23A-164).
Data list No.16
(2) 0%, (3) 0%, (4)
100%, (6) 100%Reduction
solenoid
valve duty
%Reduction
solenoid valve
system
(P.23A-174).
Data list No.9
(1) 0km/h
(4) 50km/hVehicle
speed
sensorvehicle speed
sensor system
Data list No.5
(4) 1,600
1,900
r/minInput shaft
speed
sensorInput shaft
speed sensor
system
(P.23A-55).
Data list No.6
(4) 1,600
1,900
r/minOutput
shaft speed
sensorOutput shaft
speed sensor
system
(P.23A-72).
Data list No.17
(3) 0%
(5) 70
90%Damper
control
clutch
solenoid
valve duty
%Damper control
clutch solenoid
system
(P.23A-185,
P.23A-201,
P.23A-204).
Data list No.10
(3) 100-300 rpm
(5) 0-10 rpmDamper
clutch
slippage
STEP CONDITION
BEFORE
TEST/OPERATIONTEST/OPERATION STANDARD INSPECTION
ITEMINSPECTION
PROCEDURE
PA G E

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-22
7 Transmission
range: 3 (on a
flat and straight
road)Transmission range
and vehicle speed
(1) Driving at speed
of 60 km/h in 3rd
gear
(2) Driving at
constant speed of 60
km/h
(3) Release
accelerator pedal
(Speed under 50
km/hData list No.17
(2) 70
99.6%
(3) 70
99.6% to 0%Damper
control
clutch
solenoid
valve duty
%Damper control
clutch solenoid
system
(P.23A-185,
P.23A-201,
P.23A-204).
Data list No.10
(2) 100 to 300 r/min
(3) The value
changes from (2)Damper
control
clutch
amount of
slippage
8 Use the
diagnostic tool
MB991958
(MUT-III sub
assembly) to
stop the
INVECS-II
function
Transmission
range: D (on a
flat and straight
road)(1)Accelerate to 5th
gear at a throttle
position sensor
output of 1.5 V
(accelerator opening
angle of 25%)
(2)Slowly decelerate
to a stop
(3)Accelerate to 5th
gear at a throttle
position sensor
output of 2.5 V
(accelerator opening
angle of 50%)Data list No.11, 6
The shifting points
correspond with the
diagnostic tool
display and the TP
sensor voltage
(opening angle) and
output shaft speed,
which are shown in
the standard shift
patternMalfunction
when
shiftingShift shock and
slipping
(P.23A-236).
Does not
shift
according
to
instructionsEarly or late
shifting in all
gears
(P.23A-239).
Early or late
shifting in some
gears
(P.23A-242).
STEP CONDITION
BEFORE
TEST/OPERATIONTEST/OPERATION STANDARD INSPECTION
ITEMINSPECTION
PROCEDURE
PA G E

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-23
Does not
shiftNo diagnostic
trouble code
(P.23A-244).
Input shaft
speed sensor
system
(P.23A-55).
Output shaft
speed sensor
system
(P.23A-72).
8 Use the
diagnostic tool
MB991958
(MUT-III sub
assembly) to
stop the
INVECS-II
function
Transmission
range: D (on a
flat and straight
road)(1) Accelerate from
1st gear to 5th gear.
(2) While driving at
60 km/h in 5th gear,
downshift to 4th gear
(3) While driving at
40 km/h in 4th gear,
downshift to 3rd gear
(4) While driving at
30 km/h in 3rd gear,
downshift to 2nd gear
(5) While driving at
20 km/h in 2nd gear,
downshift to 1st gearData list No.11
(1) 1st
2nd 3rd
4th 5th
(2) 5th
4th
(3) 4th
3rd
(4) 3rd
2nd
(5) 2nd
1stDoes not
shift from 1
to 2 or 2 to
1Low-reverse
solenoid valve
system
(P.23A-133).
Second
solenoid valve
system
(P.23A-154).
1st gear
incorrect ratio
(P.23A-196).
2nd gear
incorrect ratio
(P.23A-196).
Does not
shift from 2
to 3 or 3 to
2Second
solenoid valve
system
(P.23A-154).
Overdrive
solenoid valve
system
(P.23A-164).
2nd gear
incorrect ratio
(P.23A-196).
STEP CONDITION
BEFORE
TEST/OPERATIONTEST/OPERATION STANDARD INSPECTION
ITEMINSPECTION
PROCEDURE
PA G E

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-24
3rd gear
incorrect ratio
(P.23A-196).
Does not
shift from 3
to 4 or 4 to
3Low-reverse
solenoid valve
system
(P.23A-133).
Reduction
solenoid valve
system
(P.23A-154).
3rd gear
incorrect ratio
(P.23A-196).
4th gear
incorrect ratio
(P.23A-196).
Does not
shift from 4
to 5 or 5 to
4Underdrive
solenoid valve
system(
23A-200).
Second
solenoid valve
system
(P.23A-154).
4th gear
incorrect ratio
(P.23A-196).
5th gear
incorrect ratio
(P.23A-196).
STEP CONDITION
BEFORE
TEST/OPERATIONTEST/OPERATION STANDARD INSPECTION
ITEMINSPECTION
PROCEDURE
PA G E

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-25
TORQUE CONVERTER STALL TESTM1231005400362
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,
starter motor and one-way clutch operation, as well as the hold-
ing performance of the clutches and brakes in the transmission.
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 80C
Engine coolant temperature: 80 100C
NOTE: Measures transmission fluid temperature with
diagnostic tool MB991958 (MUT-III sub assembly).
2. Check both rear wheels.
3. Pull the parking brake lever on, with the brake pedal fully
depressed.
4. Start the engine. 9 Transmission
range: N (on a
flat and straight
road)Monitor data list
No.22 and No.23
with the diagnostic
tool MB991958
(MUT-III sub
assembly)
(1) Move selector
lever to R range,
drive at constant
speed of 10 km/hThe ratio between
data list No.22 and
No.23 should be the
same as the gear
ratio when reversing.Does not
shiftInput shaft
speed sensor
system
(P.23A-55).
Output shaft
speed sensor
system
(P.23A-72).
Reverse gear
incorrect ratio
(P.23A-196).
STEP CONDITION
BEFORE
TEST/OPERATIONTEST/OPERATION STANDARD INSPECTION
ITEMINSPECTION
PROCEDURE
PA G E

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-26
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, 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
or less.
5. Move the selector lever to the "D" position. Fully depress the
accelerator pedal and read the maximum engine speed at
this time.
Standard value: Stall speed: 2,100
2,600 r/min
6. Move the selector lever to the "R" position. Fully depress the
accelerator pedal and read the maximum engine speed.
Standard value: Stall speed: 2,100
2,600 r/min
TORQUE CONVERTER STALL TEST JUDGMENT
RESULTS
1. Stall speed is too high in both "D" and "R" range
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
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 TESTSM1231005500392
The transmission fluid temperature should be between 70
80C 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 80C
Engine coolant temperature: 80 100C
2. Raise the vehicle so that the wheels are free to turn.

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-27
3. Connect the special tools (3.0 MPa (427 psi) oil pressure
gauge [MD998330] and adapters [MD998332, MD998900])
to each pressure discharge port.
NOTE: .
2ND: Second brake pressure port
UD: Underdrive clutch pressure port
LR: Low-reverse brake pressure port
DR: Torque converter release pressure port
DA: Torque converter apply pressure port
RV: Reverse clutch pressure port
OD: Overdrive clutch pressure port
DIR: Direct clutch pressure port
RED: Reduction clutch pressure port
4. Restart the engine.
5. Check that there are no leaks around the special tool port
adapters.
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.