Mitsubishi Galant (2004+). Manual - part 670

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-231

STEP 11. Check PCM connector B-21 and A/T control 
solenoid valve assembly connector B-108 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.

Q: Are the connectors and terminals in good condition?

YES : Go to Step 12.
NO :  Repair or replace the damaged components. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-2

.

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-232

STEP 12. Check the harness for an open or short circuit to 
ground between PCM connector B-21 (terminals 65, 66 and 
55) and A/T control solenoid valve assembly connector 
B-108 (terminals 3, 4 and 5).

Q: Are the harness wires in good condition?

YES : Go to Step 13.
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-233

STEP 13. Check the harness for an open or short circuit to 
ground between A/T control solenoid valve assembly 
connector B-108 (terminals 3, 4, 5, and 9) and solenoid 
valve connectors B-108-1, B-108-2 and B-108-3.

Q: Is the harness wire in good condition?

YES : Replace the PCM.
NO :  Replace the harness wire.

DTC 36 (P0743): Torque Converter Clutch Solenoid Valve System

.

Solenoid Valve System Circuit
 Refer to 

P.23A-188

.

.

CIRCUIT OPERATION
 Refer to 

P.23A-188

.

.

DESCRIPTIONS OF MONITOR METHODS

• If lock-up is not engaged, and solenoid terminal 

voltage is below specified value, PCM judges that 
torque converter clutch solenoid valve has a fail-
ure.

.

MONITOR EXECUTION

• Continuous

.

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 31 (P0753): Low-reverse solenoid malfunc-

tion

• 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)

• Low-reverse solenoid

• Underdrive solenoid

• Second solenoid

• Overdrive solenoid

• A/T control relay

.

AC306322

CONNECTOR: B-108

B-108 (GR)

AC

TRANSMISSION
RANGE SWITCH

2

7

1

8

3

9

4

6

10

5

AC002219

CONNECTORS: B-108-1, B-108-2, B-108-3     

CD

B-108-1

B-108-2

B-108-3

VALVE BODY
ASSEMBLY

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-234

LOGIC FLOW CHARTS (Monitor Sequence)

.

DTC SET CONDITIONS

Check Conditions

• Solenoid status: either solid ON or OFF.

• Voltage of battery: 10 volts or more.

Judgement Criteria

• Solenoid voltage: 3 volts or less. (0.3 second)

• If DTC 36 (P0743) is set consecutively four times, 

the transaxle is locked into 3rd gear as a fail-safe 
measure, and the "N" range light flashes once 
per second.

.

OBD-II DRIVE CYCLE PATTERN
Start the engine, and keep the vehicle stopped in "P" 
range for 5 seconds.

.

TROUBLESHOOTING HINTS (The most likely 
causes for this code to be set are:)

• Malfunction of the torque converter clutch sole-

noid valve

• Damaged harness or connector

• Malfunction of the PCM

AC205240

START

END

TCC solenoid is in ON 
or OFF steady state

Voltage of battery > 10 V

Solenoid circuit 
voltage < 3 V

Continuous failure 
for 0.3 sec.

Good

Malfunction

Yes

No

Yes

No

Yes

No

Yes

No

TCC solenoid valve is in 
ON or OFF steady state

AC