Mitsubishi Montero Sport (2004+). Manual - part 636

AUTOMATIC TRANSMISSION DIAGNOSIS

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AUTOMATIC TRANSMISSION

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STEP 15. Check PCM connector C-90 for loose, corroded 
or damaged terminals, or terminals pushed back in the 
connector.

Q: Are the connector and terminals in good condition?

YES : Replace the PCM.
NO :  Repair or replace the damaged components. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-2

.

PCM

60

46

66

57

45

44

64

55 56

65

62 63

52 53

5051

61

42

59

48

41
47
58

43
49

54

AC202313

C-90 (GR)

AB

CONNECTOR: C-90

C-90 (GR)

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STEP 16. Using an oscilloscope, check the output shaft 
speed sensor waveform at PCM connectors C-90 and C-92 
by backprobing.

(1) Do not disconnect connectors C-90 and C-92.

(2) Connect an oscilloscope probe to PCM connector C-90 

terminal 57 and to PCM connector C-92 terminal 104 by 
backprobing.

(3) Start the engine and drive the vehicle at constant speed of 

50 km/h (31 mph) (Gear range: 3rd gear).

(4) Check the output shaft speed sensor waveform.

• The output shaft speed sensor waveform should show a 

pattern similar to the illustration. The maximum value 
should be 4.8 volts and more and the minimum value 
0.8 volt and less. The output waveform should not con-
tain electrical noise.

(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the waveform normal?

YES : Go to Step 19.
NO :  Go to Step 17.

AC202316

PCM

60

46

26

57

45

44

64

55 56

65

62 63

52 53

5051

61

42

59

48

41
47
58

43
49

54

120

107

119

106

129 130

118

105

117

114115116

126127128

104

111

103

112

108

101102

109110

121122123

124

113

125

CONNECTORS: C-90, C-92

AB

C-90

C-92

C-90 (GR)

C-92 (GR)

AC001900

C-92 HARNESS CONNECTOR:
 HARNESS SIDE

C-90 HARNESS CONNECTOR:
 HARNESS SIDE

AH

OSCILLO-
SCOPE

PROBE

AC001900

ACX02131

NORMAL WAVEFORM

AD

(V)

5

0

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STEP 17. Replace the output shaft speed sensor.

(1) Replace the output shaft speed sensor. Refer to GROUP 

23B, Transmission 

P.23B-19

.

(2) Test drive the vehicle.
(3) Check for A/T diagnostic trouble code.
Q: Is A/T DTC 23 set?

YES : Go to Step 18.
NO :  The procedure is complete.

STEP 18. Replace the output shaft.

(1) Replace the output shaft. Refer to GROUP 23B, 

Transmission 

P.23B-19

.

(2) Test drive the vehicle.
(3) Check for A/T diagnostic trouble code.
Q: Is A/T DTC 23 set?

YES : An A/T DTC may have set due to external radio 

frequency interference (RFI) possibility caused by 
cellular phone activity, or aftermarket components 
installed on the vehicle.

NO :  The procedure is complete.

AC002610AE

OUTPUT SHAFT
SPEED SENSOR

AC103774

OUTPUT SHAFT

AC

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STEP 19. Using scan tool MB991958, check data list item 
23: Output Shaft Speed Sensor.

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Start the engine.
(3) Set scan tool MB991958 to data-reading mode.

• Item 23: Output Shaft Speed Sensor.

• When driving at constant speed of 50 km/h (31 

mph), the display should be "1,400 

− 1,700 r/min" 

(Gear range: 3rd gear).

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

− How to 

Cope with Intermittent Malfunction 

P.00-7

.

NO :  Replace the PCM.

AK303629AB

MB991911

MB991827

MB991824 

16-PIN