Mitsubishi Galant (2004+). Manual — part 659

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-187

STEP 20. Using scan tool MB991958, check data list item
61: Transmission Range Switch.

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) Turn the ignition switch to the "ON" position.
(3) Set scan tool MB991958 to data reading mode.

• Item 61: Transmission Range Switch.

• Move the selector lever to "P," "R," "N," "D" and sport

mode positions and confirm that the selected trans-
mission ranges match the positions. (Sport mode is
indicated as "D" on the scan tool MB991958).

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the switch 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.00-6

.

NO : Replace the PCM.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AUTOMATIC TRANSAXLE DIAGNOSIS

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AUTOMATIC TRANSAXLE

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DTC 31 (P0753): Low-Reverse Solenoid Valve System

BATTERY

RELAY
BOX

A/T
CONTROL
RELAY

A/T CONTROL
SOLENOID
VALVE ASSEMBLY

POWERTRAIN
CONTROL MODULE

UNDERDRIVE
SOLENOID
VALVE

SECOND
SOLENOID
VALVE

OVERDRIVE
SOLENOID
VALVE

TORQUE
CONVERTER
CLUTCH
CONTROL
SOLENOID
VALVE

LOW AND
REVERSE
SOLENOID
VALVE

AC209759AC

Solenoid Valve System Circuit

AUTOMATIC TRANSAXLE DIAGNOSIS

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AUTOMATIC TRANSAXLE

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.

CIRCUIT OPERATION

• The A/T control relay supplies battery positive

voltage to the solenoid valve assembly (terminals
9 and 10).

• The solenoid valve closes when energized (on),

and opens when not energized (off). The PCM
energizes the solenoid valve based on input data
from sensors such as the Throttle Position Sen-
sor, Transmission Range Switch, Stoplight
Switch, Input Shaft Speed Sensor, Output Shaft
Speed Sensor, and Transmission Fluid Tempera-
ture Sensor.

• The PCM provides the ground to energize the

solenoid. The amount of time that the circuit is
grounded is displayed on scan tool MB991958 in
percent.

• When the solenoid is energized or de-energized,

fluid passes through the valve body and transaxle
passages to apply and release components.

.

DESCRIPTIONS OF MONITOR METHODS

• If solenoid terminal voltage is below specified

value when shift control is not in progress, PCM
judges that low-reverse solenoid valve has a fail-
ure.

.

MONITOR EXECUTION

• Continuous

.

AC306223

A-13 (GR)

AB

CONNECTOR: A-13

1

4

7

8

2 3

5

13

14

17

15

12

16

11

10

9

6

AC306354

RELAY BOX

AB

CONNECTOR: B-16X

2

1

3

4

FRONT OF
VEHICLE

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

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AUTOMATIC TRANSAXLE

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MONITOR EXECUTION CONDITIONS (Other
monitor and Sensor)

Other Monitor (There is no temporary DTC stored

in memory for the item monitored below)

• DTC 41 (P0731): 1st gear incorrect ratio

• DTC 42 (P0732): 2nd gear incorrect ratio

• DTC 43 (P0733): 3rd gear incorrect ratio

• DTC 44 (P0734): 4th gear incorrect ratio

• DTC 46 (P0736): Reverse gear incorrect ratio

• DTC 36 (P0743): Torque converter clutch sole-

noid malfunction

• DTC 32 (P0758): Underdrive solenoid malfunc-

tion

• DTC 33 (P0763): Second solenoid malfunction

• DTC 34 (P0768): Overdrive solenoid malfunction

• DTC 54 (P1751): A/T control relay malfunction

Sensor (The sensor below is determined to be

normal)

• Torque converter clutch solenoid

• Underdrive solenoid

• Second solenoid

• Overdrive solenoid

• A/T control relay

.

LOGIC FLOW CHARTS (Monitor Sequence)

.

AC205281

Good

Malfunction

END

START

In-gear?

Shift solenoid-A is in ON
or OFF steady state

Voltage of battery > 10 V

Solenoid circuit
voltage < 3 V

Continuous failure
for 0.3 sec.

Yes

No

Yes

No

Yes

No

Yes

No

Yes

No

Low-reverse solenoid valve
is in ON or OFF steady state

AB