Mitsubishi Pajero Pinin. Manual - part 179

AUTOMATIC TRANSMISSION – 

Troubleshooting <A/T>

23-26

INSPECTION PROCEDURE 16

Stop lamp switch system

Probable cause

If large shocks occur during squat control, the cause is probably a problem with
the stop lamp switch.

D

Malfunction of stop lamp switch

D

Malfunction of harness or connector

D

Malfunction of A/T-ECU

MUT-

II

 SERVICE DATA

D

28 – Stop lamp switch
OK: ON when the brake pedal is

depressed and OFF when the
brake pedal is released

OK

Check the stop lamp switch 
(Refer to GROUP 35 – Brake Pedal)

NG

Check the following connectors:
<L.H. drive vehicles> C-04, C-02, C-29,
C-24, D-02, D-04
<R.H. drive vehicles> C-04, C-02, C-41,
D-02, D-04

NG

Repair

OK

Check the harness wire between the
stop lamp switch and the A/T-ECU.

Repair

OK

Check the trouble symptoms.

NG

Replace the A/T-ECU.

AUTOMATIC TRANSMISSION – 

Troubleshooting <A/T>

23-27

SERVICE DATA REFERENCE TABLE

Item
No.

Inspection item

Inspection conditions

Normal value

13

Accelerator
pedal position
sensor (throttle

Engine: Idle
Selector lever position: N

Accelerator pedal: Fully
released

0 – 5 %

sensor (throttle
opening voltage)

Accelerator pedal: Depressed

Gradually rises from
the above value

Accelerator pedal: Fully
depressed (up to 2 seconds)

85 – 100 %

14

Accelerator
pedal position

Ignition switch: ON
Engine: Stopped

Ignition switch: ON

Approx. 5 V

edal  osition

sensor (power
supply voltage)

Engine: Sto

ed

Ignition switch: OFF

0   V

15

A/T fluid 
temperature
sensor

Driving with engine
warmed up

Drive for 15 minutes or more
until the A/T fluid temperature is
70 – 90

_

C.

Gradually increases
to 70 – 90

_

C

22

Wide open
throttle switch

Accelerator pedal position

Released

OFF

throttle switch

Depressed

ON

27

Shift position
signal

Accelerator pedal: Fully
released
Engine: Idle (Vehicle
stopped)
Selector lever position: N
Brake pedal: Depressed

Shifting from N to D

1st

→

3rd

→

1st

Selector lever position: L

Idle (Vehicle stopped)

1st

Selector lever position: 2

Idle (Vehicle stopped)

1st

Driving at 40 km/h (20 seconds
or more)

2nd

Selector lever position: D
Overdrive switch: OFF

Driving at constant speed of 50
km/h (20 seconds or more)

3rd

Selector lever position: D
Overdrive switch: OFF

Driving at constant speed of 50
km/h (20 seconds or more)

4th

28

Stop lamp switch

Ignition switch: ON
Engine: Stopped

Brake pedal: Depressed

ON

Engine: Stopped

Brake pedal: Released

OFF

31

Input shaft speed
sensor

Selector lever position: D
Overdrive switch: OFF

Driving at constant speed of 50
km/h

1,800 – 2,000 r/min

32

Output shaft
speed sensor

Selector lever position: D
Overdrive switch: OFF

Driving at constant speed of 50
km/h

1,800 – 2,000 r/min

35

Overdrive switch

Ignition switch: ON
Engine: Stopped

Overdrive switch: OFF

OD-OFF

Engine: Stopped

Overdrive switch: ON

OD

AUTOMATIC TRANSMISSION – 

Troubleshooting <A/T>

23-28

Item
No.

Inspection item

Inspection conditions

Normal value

37

Inhibitor switch

Ignition switch: ON
Engine: Stopped

Selector lever position: P

P, R, D

Engine: Stopped

Selector lever position: R

P, R, D

Selector lever position: N

N

Selector lever position: D

P, R, D

Selector lever position: 2

2

Selector lever position: L

L

38

Vehicle speed
sensor

Selector lever 
position: L, D
Overdrive switch: OFF

Idling in 1st gear (Vehicle
stopped)

0 r/min

Overdrive switch: OFF

Driving at constant speed of 50
km/h (3rd gear)

450 – 550 r/min

41

Solenoid valve
No. 1

Selector lever position: D
Overdrive switch: ON

Driving at constant speed of 5
km/h (1st gear)

ON

Driving at constant speed of 50
km/h (4th gear)

OFF

43

Solenoid valve
No. 2

Selector lever position: D
Overdrive switch: OFF

Driving at constant speed of 5
km/h (1st gear)

OFF

Driving at constant speed of 50
km/h (3rd gear)

ON

47

Solenoid valve
No. 3

Selector lever position: D
Overdrive switch: ON

Driving at constant speed of 5
km/h (1st gear)

OFF

Driving at constant speed of 50
km/h (4th gear)

ON

53

N range switch

Ignition switch: ON
Engine: Stopped

Selector lever position: N

ON

Engine: Stopped

Selector lever position: Other
than N

OFF

55

2 range switch

Selector lever position: 2

ON

Selector lever position: Other
than 2

OFF

56

L range switch

Selector lever position: L

ON

Selector lever position: Other
than L

OFF

61

Free-wheeling
engage switch

Ignition switch: ON
Engine: Stopped

Transfer lever position: Other
than 4WD

4WD

Transfer lever position: 4WD

2WD

63

Dual-pressure
switch

Engine: Stopped
Selector lever position: N

A/C switch: ON

ON

switch

Selector lever position: N

A/C switch: OFF

OFF

AUTOMATIC TRANSMISSION – 

Troubleshooting <A/T>

23-29

REFERENCE FOR FAIL-SAFE/BACKUP FUNCTIONS

When malfunctions of the main sensors or actuators are detected by the diagnosis system, the vehicle
is controlled by means of the pre-set control logic to maintain safe conditions for driving.

Malfunctioning item

Control contents during malfunction

Output shaft speed
sensor

If there is an open circuit in the output shaft speed sensor, upshifting to 4th gear and lockup
control is stopped.

Inhibitor switch

If there is an open circuit in the N, 2 or L signal line, driving is possible in the case of 2 and L
(same as D range) so that control can be performed as if the range is D range, and driving is
not possible in N range. If more than one of the N, 2 or L signals are input, the order of priority
for control is L

→

2

→

N.

Accelerator pedal 
position sensor

If the output is 0.335 V or less or 4.8 V or more during idling condition, gear shifting control when
throttle is fully closed is carried out.

Solenoid valve No. 3

If a problem is detected, lockup is stopped over the whole range and the solenoid is turned off
to prevent the engine from stalling during idling.

Solenoid valve No. 1,
No. 2

If a problem is detected, each solenoid stops operating and is turned off. The gear shifting logic
when a problem is detected is given in the table below

Selector le-
ver
position

Normal

When the solenoid
valve No. 1 has broken

When the solenoid
valve No. 2 has broken

When the solenoid
valves No. 1 and No. 2
have broken

Gear

S1

S2

Gear

S1

S2

Gear

S1

S2

Gear

S1

S2

D

1

f

×

3

×→

f

1

f

O/D

2

f

f

3

f

O/D

f

→×

O/D

3

×

f

3

f

O/D

×

O/D

O/D

×

×

O/D

×

O/D

×

O/D

2

1

f

×

3

×→

f

1

f

3

2

f

f

3

f

3

f

→×

3

3

×

f

3

f

3

×

3

L

1

f

×

1

×

1

f

1

2

f

f

2

f

1

f

1

f

: Energized (ON)

×

: Not energized (OFF)