Mitsubishi 380. Manual — part 373

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-32

HYDRAULIC CIRCUIT

M1231008800336

OVERVIEW

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

R N D

P

10DB150A

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

VALVE

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

VALVE

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

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-33

LINE PRESSURE ADJUSTMENT

M1231001700361

1. Drain the transmission fluid.

NOTE: The hydraulic pressure test must be performed
before attempting any adjustments.

2. Remove the valve body cover.

3. Turn the adjusting screw shown in the illustration to adjust

the line pressure to the standard value in "D" range 1st or
2nd gear. The pressure increases when the screw is turned
counterclockwise approximately 35 kPa for each turn.

NOTE: When adjusting the line pressure, adjust to the mid-
dle of the standard value range.

Standard value: 980

− 1050 kPa

4. Install the valve body cover. Pour in the standard volume of

automatic transmission fluid.

5. Repeat the hydraulic pressure test. (Refer to

P.23A-26

).

Readjust the line pressure if necessary.

AC006153AB

ADJUSTING
SCREW

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-34

DIAGNOSTIC TROUBLE CODE CHART

M1231007900330

CAUTION

During diagnosis, a DTC code associated with
other system may be set when the ignition switch
is turned on with connector(s) disconnected. On
completion, confirm all systems for DTC code(s).
If DTC code(s) are set, erase them all.

NOTE: The A/T diagnostic trouble codes are the codes which are set when item "A/T" is selected on
diagnostic tool MB991958 (MUT-III sub assembly). However, the some codes above indicate failure in the
MPI system.

A/T DTC
NO.

DIAGNOSIS ITEM

REFERENCE
PAGE

P0713

Transmission fluid temperature sensor system

Open circuit

P.23A-36

P0712

Short circuit

P.23A-47

P0715

Input shaft speed sensor system

Short circuit/open circuit

P.23A-55

P0720

Output shaft speed sensor system

Short circuit/open circuit

P.23A-72

−

Stoplamp switch system

Short circuit

P.23A-89

P0705

Transmission range switch system

Open circuit

P.23A-97

Short circuit

P.23A-119

P0753

Low-reverse solenoid valve system

Short circuit/open circuit

P.23A-133

P0758

Underdrive solenoid valve system

Short circuit/open circuit

P.23A-144

P0763

Second solenoid valve system

Short circuit/open circuit

P.23A-154

P0768

Overdrive solenoid valve system

Short circuit/open circuit

P.23A-164

P0773

Reduction (RED) solenoid valve system

Short circuit/open circuit

P.23A-174

P0743

Damper clutch control (DCC) solenoid valve
system

Short circuit/open circuit

P.23A-185

P0731

1st gear incorrect ratio

P.23A-196

P0732

2nd gear incorrect ratio

P.23A-196

P0733

3rd gear incorrect ratio

P.23A-196

P0734

4th gear incorrect ratio

P.23A-196

P0735

5th gear incorrect ratio

P.23A-196

P0736

Reverse gear incorrect ratio

P.23A-196

P0741

Damper clutch control (DCC) system

Defective system

P.23A-201

P0742

Clutch stuck on

P.23A-204

P1751

A/T control relay system

Short circuit to ground/open
circuit

P.23A-207

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-35

SYMPTOM CHART

M1231008000277

CAUTION

During diagnosis, a DTC code associated with
other system may be set when the ignition switch
is turned on with connector(s) disconnected. On
completion, confirm all systems for DTC code(s).
If DTC code(s) are set, erase them all.

SYMPTOM

INSPECTION
PROCEDURE NO.

REFERENCE
PAGE

Communication with diagnostic
tool is not possible

Communication with all systems
is impossible

-

Group 13B
Symptom
Procedures

13A-539

.

Communication with the
A/T-ECU only is impossible

-

Group 13B
Symptom
Procedures

13A-541

.

Driving impossible

Engine does not start

1

P.23A-218

Does not move forward

2

P.23A-220

Does not move backward

3

P.23A-223

Does not move (forward and
backward)

4

P.23A-226

Malfunction when moving
selector into gear

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

5

P.23A-227

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

6

P.23A-229

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

7

P.23A-232

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

8

P.23A-235

Malfunction when shifting

Shift shock and slipping

9

P.23A-236

Does not shift properly

Early or late shifting in all gears 10

P.23A-239

Early or late shifting in some
gears

11

P.23A-242

Does not shift

No diagnostic trouble codes

12

P.23A-244

Malfunction while driving

Poor acceleration

13

P.23A-248

Vibration

14

P.23A-250

Shift switch assembly system

15

P.23A-252

Shift position indicator light system <Vehicles with sport mode>

16

P.23A-269