Mitsubishi Galant (2004+). Manual - part 626

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-55

STEP 9. Measure the sensor output voltage at PCM 
connector B-21 by using check harness special tool 
MB991923 .

(1) Disconnect all the connectors from the PCM.

(2) Connect special tool MB991923 (check harness) between 

the PCM and the body-side harness connector.

(3) Turn the ignition switch to the "ON" position.

AC306248AC

B-21 
(B)

CONNECTOR: B-21

PCM

AIR
CLEANER

73

80

54

67

60

71 72

77 78 79

64

51

59

58

65

52

66

53

75

74

76

81 82

83

63

JAE

62

68

61

55

69

56

70

57

AC209793AG

SPECIAL TOOL 33-PIN CONNECTOR
(PCM CONNECTOR B-21)

B-21
(GR)

55

56

54 53 52 51

57

62 61 60 59 58

63

69 68 67 66 65 64

70

75 74 73 72 71

76

82 81 80 79 78 77

83

PCM

MB991923

BODY SIDE
HARNESS

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-56

(4) Measure the voltage between terminal 74 and ground.

• When transmission fluid temperature is 20°C (68°F), 

voltage should measure between 3.8 and 4.0 volts.

• When transmission fluid temperature is 40°C (104°F), 

voltage should measure between 3.2 and 3.4 volts.

• When transmission fluid temperature is 80°C (176°F), 

voltage should measure between 1.7 and 1.9 volts.

(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage within the specified range?

YES : Go to Step 6.
NO :  Go to Step 10.

STEP 10. Check PCM connector B-21 for loose, corroded 
or damaged terminals, or terminals pushed back in the 
connector.

Q: Are the connector and terminals in good condition?

YES : Go to Step 11.
NO :  Repair or replace the damaged components. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-2

.

AC210334

51

58

71

64

77

76

83

70

63

57

73 72

75 74

80

82 81

79 78

54

67

JAE

62

69

56

61

68

55

59

66

60

53

65

52

AD

B-21 HARNESS 
CONNECTOR:
COMPONENT SIDE

AC306248AC

B-21 
(B)

CONNECTOR: B-21

PCM

AIR
CLEANER

73

80

54

67

60

71 72

77 78 79

64

51

59

58

65

52

66

53

75

74

76

81 82

83

63

JAE

62

68

61

55

69

56

70

57

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-57

STEP 11. Check the harness for open circuit or short 
circuit to ground between PCM connector B-21 terminal 74 
and A/T control solenoid valve connector B-108 terminal 1.

Q: Is the harness wire in good condition?

YES : Go to Step 6.
NO :  Repair or replace the harness wire.

AC306248AC

B-21 
(B)

CONNECTOR: B-21

PCM

AIR
CLEANER

73

80

54

67

60

71 72

77 78 79

64

51

59

58

65

52

66

53

75

74

76

81 82

83

63

JAE

62

68

61

55

69

56

70

57

AC306322

CONNECTOR: B-108

B-108 (GR)

AC

TRANSMISSION
RANGE SWITCH

2

7

1

8

3

9

4

6

10

5

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-58

STEP 12. Measure the ground voltage at PCM connector 
B-21 by using check harness special tool MB991923.

(1) Disconnect all the connectors from the PCM.

(2) Connect special tool MB991923 (check harness) between 

the PCM and the body-side harness connector.

(3) Turn the ignition switch to the "ON" position.

AC306248AC

B-21 
(B)

CONNECTOR: B-21

PCM

AIR
CLEANER

73

80

54

67

60

71 72

77 78 79

64

51

59

58

65

52

66

53

75

74

76

81 82

83

63

JAE

62

68

61

55

69

56

70

57

AC209793AG

SPECIAL TOOL 33-PIN CONNECTOR
(PCM CONNECTOR B-21)

B-21
(GR)

55

56

54 53 52 51

57

62 61 60 59 58

63

69 68 67 66 65 64

70

75 74 73 72 71

76

82 81 80 79 78 77

83

PCM

MB991923

BODY SIDE
HARNESS