Mitsubishi Montero (2004+). Manual - part 863

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-27

STANDARD HYDRAULIC PRESSURE TEST

NOTE: When the torque converter clutch pressure is measured, the engine speed should be 1,500 r/min or 
less.

HYDRAULIC PRESSURE TEST DIAGNOSIS TABLE

MEASUREMENT CONDITION STANDARD HYDRAULIC PRESSURE MPa (psi)

TRANS-
MISSION 
RANGE

SHIFT 
POSI-
TION

ENGINE 
SPEED 
(r/min)

UNDER-
DRIVE 
CLUTCH 
PRES-
SURE [UC]

REVERSE 
CLUTCH 
PRES-
SURE 
[RC]

OVER-
DRIVE 
CLUTCH 
PRES-
SURE [OC]

DIRECT 
CLUTCH 
PRES-
SURE [DC]

LOW- 
RE-
VERSE 
BRAKE 
PRES-
SURE 
[LB]

SECOND 
BRAKE 
PRES-
SURE [2B]

REDUC-
TION 
BRAKE 
PRES-
SURE 
[RB]

TORQUE 
CON-
VERTER 
CLUTCH 
PRES-
SURE 
[TR]

P

−

2,500

−

−

−

−

0.26 

− 

0.36 (38 
− 52)

−

0.26 

− 

0.36 (38 
− 52)

0.22 

− 

0.36 (32 
− 52)

R

Reverse

2,500

−

1.27 

− 

1.77 (185 
− 256)

−

−

1.27 

− 

1.77 (185 
− 256)

−

1.27 

− 

1.77 (185 
− 256)

0.50 

− 

0.73 (73 
− 106)

N

−

2,500

−

−

−

−

0.26 

− 

0.36 (38 
− 52)

−

0.26 

− 

0.36 (38 
− 52)

0.22 

− 

0.36 (32 
− 52)

Sport 
mode

1st gear

2,500

0.98 

− 1.05 

(142 

− 152)

−

−

−

0.98 

− 

1.05 (142 
− 152)

−

0.98 

− 

1.05 (142 
− 152)

0.50 

− 

0.73 (73 
− 106)

2nd gear 2,500

0.98 

− 1.05 

(142 

− 152)

−

−

−

−

0.98 

− 1.05 

(142 

− 152)

0.98 

− 

1.05 (142 
− 152)

0.50 

− 

0.73 (73 
− 106)

3rd gear

2,500

0.78 

− 0.90 

(113 

− 131)

−

0.78 

− 0.90 

(113 

− 131)

−

−

−

0.78 

− 

0.88 (113 
− 128)

0.45 

− 

0.72 (65 
− 104)

4th gear

2,500

0.78 

− 0.90 

(113 

− 131)

−

0.78 

− 0.90 

(113 

− 131)

0.78 

− 0.88 

(113 

− 128)

−

−

−

0.45 

− 

0.72 (65 
− 104)

5th gear

2,500

−

−

0.78 

− 0.90 

(113 

− 131)

0.78 

− 0.88 

(113 

− 128)

−

0.78 

− 0.88 

(113 

− 128)

−

0.45 

− 

0.72 (65 
− 104)

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

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-28

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

Only underdrive clutch hydraulic 
pressure is abnormal.

Malfunction of the oil seal K
Malfunction of the oil seal L
Malfunction of the oil seal M
Malfunction of the oil seal Q
Malfunction of the underdrive solenoid valve
Malfunction of the underdrive pressure control valve
Malfunction of the check ball
Clogged orifice
Incorrect valve body installation

Only reverse clutch hydraulic 
pressure is abnormal.

Malfunction of the oil seal A
Malfunction of the oil seal B
Malfunction of the oil seal C
Clogged orifice
Incorrect valve body installation

Only overdrive clutch hydraulic 
pressure is abnormal.

Malfunction of the oil seal D
Malfunction of the oil seal E
Malfunction of the oil seal F
Malfunction of the overdrive solenoid valve
Malfunction of the overdrive pressure control valve
Malfunction of the check ball
Clogged orifice
Incorrect valve body installation

Only direct clutch hydraulic pressure 
is abnormal.

Malfunction of the oil seal R
Malfunction of the oil seal S
Malfunction of the oil seal T
Malfunction of the low-reverse solenoid valve (Shared with direct 
clutch)
Malfunction of the low-reverse pressure control valve
Malfunction of the switch valve
Malfunction of the fail safe valve C
Clogged orifice
Incorrect valve body installation

SYMPTOM

PROBABLE CAUSE

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-29

.

Only low-reverse brake hydraulic 
pressure is abnormal.

Malfunction of the oil seal I
Malfunction of the oil seal J
Malfunction of the oil seal P
Malfunction of the low-reverse solenoid valve
Malfunction of the low-reverse pressure control valve
Malfunction of the switch valve
Malfunction of the fail safe valve A
Malfunction of all the check ball
Clogged orifice
Incorrect valve body installation

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

Only reduction brake hydraulic 
pressure is abnormal.

Malfunction of the oil seal U
Malfunction of the oil seal V
Malfunction of the reduction solenoid valve
Malfunction of the reduction pressure control valve
Clogged orifice
Incorrect valve body installation

Only torque converter clutch pressure 
is abnormal.

Clogged oil cooler
Malfunction of the oil seal N
Malfunction of the torque converter clutch solenoid valve
Malfunction of the torque converter clutch 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

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-30

OIL SEAL LAYOUT

AC100422

N A B C D E F G H I

J K

L

M

T S

R

Q

O

P

V

U

AB

a

a

SECTION a - a