2005 MITSUBISHI 380 sensor

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-13
A/T DIAGNOSTIC TROUBLESHOOTING STRATEGYM1231007600339
Use these steps to plan your diagnostic strategy. If
you follow them carefully, you will find most A/T mal-
functions.
1. Gather as much information as possible about the
complaint from the customer.
2. Verify that the condition described by the
customer exists.
3. Check the vehicle for any A/T Diagnostic Trouble
Codes (DTCs).
4. If you can not verify the condition and there are no
DTCs, the malfunction is intermittent. For
information on how to cope with intermittent
malfunctions, refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points
How
to Cope with Intermittent Malfunction P.00-14.
5. If you can verify the condition but there are no
DTCs, or the system can not communicate with
diagnostic tool, refer to the Symptom Chart
P.23A-35.6. If there is a DTC, record the number of the code,
then erase the code from memory using
diagnostic tool.
7. Reconfirm the symptom with a Road Test.
8. If a DTC is set again, go to the Inspection Chart
for Diagnostic Trouble Codes.
9. If a DTC is not set again, the malfunction is
intermittent. For information on how to cope with
intermittent malfunctions, refer to GROUP 00,
How to Use Troubleshooting/Inspection Service
Points
How to Cope with Intermittent
Malfunction P.00-14.
10.After repairs are completed, conduct a Road Test
duplicating the complaint conditions to confirm the
malfunction has been eliminated.
DIAGNOSTIC FUNCTIONM1231022500135
CHECK "N" RANGE LIGHT
The "N" range light flashes once per second if there is an
abnormality in any of the items in the table below which are
related to the A/T system. Check for diagnostic trouble codes if
the "N" range light is flashing once per second.
NOTE: The "N" indicator lamp warning function does not
operate with the selector lever in the "P" (PARK), "R"
(REVERSE) or "N" (NEUTRAL) position.
"N" range light flashing items
Input shaft speed sensor
Output shaft speed sensor
Each solenoid valve
Gear incorrect ratio
A/T control relay system
If the "N" range light is flashing rapidly (twice per second),
the transmission fluid temperature is too high. (It flashes
when the fluid is approximately 125
C or more and goes
off when the fluid is approximately 115
C or less)
ON-BOARD DIAGNOSTICS
The automatic transmission -electronic control unit
(A/T-ECU) monitors its input/output signals (some
signals all the time and others under specified condi-
tions). When an irregular signal is initially monitored,
the A/T-ECU decides that a malfunction has
occurred and records the occurrence as a diagnostic
trouble code. The diagnostic results can be read with diagnostic tool. Diagnostic trouble codes are kept in
memory by direct battery feed. The codes are
retained in memory even if the ignition switch is in
the "LOCK" (OFF) position. DTCs are not erased
even after the battery terminals and the A/T-ECU
connector are disconnected. In addition, the diagnos-
tic trouble code can also be erased by diagnostic
tool.

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-14
NOTE: If a sensor is disconnected when the ignition
switch is in the "ON" position, a diagnostic trouble
code is stored in memory. In this case, erase the
DTC using diagnostic tool.The diagnostic items are displayed in numeric order.
HOW TO CONNECT THE DIAGNOSTIC TOOL
(MUT-III)
Required Special Tools:
MB991958: Diagnostic Tool (MUT-III Sub Assembly)
MB991824: Vehicle Communication Interface (V.C.I.)
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A
To prevent damage to diagnostic tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting diagnostic tool
MB991958.
1. Ensure that the ignition switch is at the "LOCK" (OFF)
position.
2. Start up the personal computer.
3. Connect special tool MB991827 to special tool MB991824
and the personal computer.
4. Connect special tool MB991910 to special tool MB991824.
5. Connect special tool MB991910 to the data link connector.
6. Turn the power switch of special tool MB991824 to the "ON"
position.
NOTE: When special tool MB991824 is energized, special
tool MB991824 indicator light will be illuminated in a green
color.
7. Start the MUT-III system on the personal computer.
NOTE: Disconnecting diagnostic tool MB991958 is the reverse
of the connecting sequence, making sure that the ignition
switch is at the "LOCK" (OFF) position.
HOW TO READ AND ERASE DIAGNOSTIC
TROUBLE CODES
Required Special Tools:
MB991958: Diagnostic Tool (MUT-III Sub Assembly)
MB991824: V.C.I.
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A

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-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-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