Page 1485 of 1500

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.
Page 1486 of 1500
![MITSUBISHI 380 2005 Workshop Manual 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 discha MITSUBISHI 380 2005 Workshop Manual 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 discha](/manual-img/19/57086/w960_57086-1485.png)
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.
Page 1487 of 1500

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-28
STANDARD HYDRAULIC PRESSURE TABLE
NOTE: When the torque converter pressure is measured, the engine speed should be 1,500 r/min or less.
HYDRAULIC PRESSURE TEST DIAGNOSIS TABLE
MEASUREMENT
CONDITIONSSTANDARD HYDRAULIC PRESSURE kPa
SELECT-
OR
LEVER
POS’N SHIFT
RANGE
POSITIO
NENGINE
SPEED
(r/min)UNDERDRIVE
CLUTCH
PRESSURE
[UD]REVERSE
CLUTCH
PRESSURE
[RV]OVERDRIVE
CLUTCH
PRESSURE
[OD]DIRECT
CLUTCH
PRESSURE
[DIR]LOW-
REVERSE
BRAKE
PRESSURE
[LR]SECOND
BRAKE
PRESSURE
[2ND]TORQUE
CONVERTER
PRESSURE
[DR]
P2,500260 360260 360
R Rev. 2,500
12701770 12701770 500 730
N
2,500260 360 220 360
Spo rt
mode1st 2,500 980
1050 980 1050 500 730
2nd 2,500 980
1050 980 1050 500 730
3rd 2,500 780
900 780 900 450 720
4th 2,500 780
900 780 900 780 880 450 720
5th 2,500
780 900 780 880 780 880 450 720
SYMPTOM PROBABLE CAUSE
All hydraulic pressures are high. Malfunction of the regulator valve
All hydraulic pressures are low. Malfunction of the oil pump
Clogged internal oil filter
Clogged oil cooler
Malfunction of the regulator valve
Malfunction of the relief valve
Incorrect valve body installation
Improperly installed solenoid valves
Damaged solenoid valve O-rings
Hydraulic pressure is abnormal
in reverse gear only.Malfunction of the regulator valve
Clogged orifice
Incorrect valve body installation
Hydraulic pressure is abnormal
in 3rd or 4th gear only.Malfunction of the overdrive solenoid valve
Malfunction of the overdrive pressure control valve
Malfunction of the regulator valve
Malfunction of the switch valve
Clogged orifice
Incorrect valve body installation
Page 1489 of 1500

AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-30
Only second brake hydraulic
pressure is abnormal.Malfunction of the oil seal G
Malfunction of the oil seal H
Malfunction of the oil seal O
Malfunction of the second solenoid valve
Malfunction of the second pressure control valve
Malfunction of the fail safe valve B
Clogged orifice
Incorrect valve body installation
Malfunction of the accumulator for second brake
Only reduction brake hydraulic
pressure is abnormal.Malfunction of the oil seal U or V
Malfunction of the reduction solenoid valve
Malfunction of the reduction pressure control valve
Clogged orifice
Incorrect valve body installation
Only torque converter pressure
is abnormal.Clogged oil cooler
Malfunction of the oil seal N
Malfunction of the torque converter clutch solenoid
Malfunction of the torque converter pressure control valve
Clogged orifice
Incorrect valve body installation
Pressure applied to element
which should not receive
pressure.Incorrect transmission control cable adjustment
Malfunction of the manual valve
Malfunction of the check ball
Incorrect valve body installation SYMPTOM PROBABLE CAUSE
Page 1491 of 1500
AUTOMATIC TRANSMISSION DIAGNOSIS
AUTOMATIC TRANSMISSION23A-32
HYDRAULIC CIRCUITM1231008800336
OVERVIEW
1. REVERSE CLUTCH
2. LOW-REVERSE BRAKE
3. SECOND BRAKE
4. UNDERDRIVE CLUTCH
5. OVERDRIVE CLUTCH
6. RED CLUTCH
7. DIR CLUTCH
8. TORQUE CONVERTER CLUTCH
9. FAIL SAFE VALVE A
10. FAIL SAFE VALVE B
11. FAIL SAFE VALVE C
12. SWITCH VALVE
13. TRANSMISSION FLUID COOLER
14. TORQUE CONVERTER CLUTCH CONTROL
VA LV E
15. LOW-REVERSE PRESSURE CONTROL VALVE
16. SECOND PRESSURE CONTROL VALVE
17. UNDERDRIVE PRESSURE CONTROL VALVE
18. OVERDRIVE PRESSURE CONTROL VALVE 19. RED PRESSURE CONTROL VALVE
20. TORQUE CONVERTER CLUTCH SOLENOID
VA LV E
21. LOW-REVERSE SOLENOID VALVE
22. SECOND SOLENOID VALVE
23. UNDERDRIVE SOLENOID VALVE
24. OVERDRIVE SOLENOID VALVE
25. RED SOLENOID VALVE
26. TORQUE CONVERTER PRESSURE
CONTROL VALVE
27. REGULATOR VALVE
28. MANUAL VALVE
29. OIL STRAINER
30. OIL FILTER
31. OIL PUMP
32. OIL FILTER
33. RELIEF VALVE
34. OIL PAN