Mitsubishi Galant (2004+). Manual - part 660

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-191

DTC SET CONDITIONS

Check Conditions

• Solenoid status: either solid ON or OFF.

• Shift status: in-gear.

• Voltage of battery: 10 volts or more.

Judgement Criteria

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

• If DTC 31 (P0753) 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 low-reverse solenoid valve

• Damaged harness or connector

• Malfunction of the PCM

DIAGNOSIS

Required Special Tool:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: MUT-III USB Cable

• MB991910: MUT-III Main Harness A

STEP 1. Using scan tool MB991958, check actuator test 
item 01: Low-Reverse Solenoid Valve.

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 the actuator test mode.

• Item 01: Low-Reverse Solenoid Valve.

• An audible clicking or buzzing should be heard when 

the low-reverse solenoid valve is energized.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the solenoid valve 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 Malfunctions 

P.00-6

.

NO :  Go to Step 2.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-192

STEP 2. Using scan tool MB991958, read the A/T 
diagnostic trouble code.

(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Check for A/T diagnostic trouble code.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC 54 set? (DTC 54 may be set along with multiple 

DTCs).
YES : Refer to 

P.23A-267

 DTC 54: A/T Control Relay 

System.

NO :  Go to Step 3.

STEP 3. Using scan tool MB991958, read the A/T 
diagnostic trouble code.

(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.

(3) Check for A/T diagnostic trouble code.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC 36 set?

YES : Go to Step 8.
NO :  Go to Step 4.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-193

STEP 4. Measure the low-reverse solenoid valve resistance 
at A/T control solenoid valve assembly connector B-108.

(1) Disconnect connector B-108 and measure at the solenoid 

valve side.

(2) Measure the resistance between solenoid valve assembly 

connector B-108 terminals 6 and 10.

Resistance value: 2.7

−3.4 Ω [at 20°C (68°F)]

Q: Is the measured resistance 2.7

−3.4 Ω [at 20°C (68°F)]?

YES : Go to Step 6.
NO :  Go to Step 5.

STEP 5. Measure the solenoid valve resistance at the 
low-reverse solenoid valve assembly inside the transaxle.

(1) Disconnect connector B-108-5 and measure at the solenoid 

valve side.

(2) Measure the resistance between low-reverse solenoid 

valve terminals 1 and 2.

Resistance value: 2.7

−3.4 Ω [at 20°C (68°F)]

Q: Is the measured resistance 2.7

−3.4 Ω [at 20°C (68°F)?

YES : Replace the harness wire between A/T control 

solenoid valve assembly connector B-108 and the 
solenoid valves.

NO :  Replace the low-reverse solenoid valve. Refer to 

GROUP 23B, Valve Body 

P.23B-79

.

AC306322

CONNECTOR: B-108

B-108 (GR)

AC

TRANSMISSION
RANGE SWITCH

2

7

1

8

3

9

4

6

10

5

AC210673

2

7

1

8

3

9

4

6

10

5

B-108 HARNESS CONNECTOR:
A/T CONTROL SOLENOID
VALVE ASSEMBLY SIDE

AB

AC002219

CONNECTOR: B-108-5

CB

B-108-5

VALVE BODY
ASSEMBLY

2

1

AC201141AZ

B-108-5 HARNESS CONNECTOR: 
LOW-REVERSE
SOLENOID VALVE SIDE

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-194

STEP 6. 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 7.
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