Mitsubishi Galant (2004+). Manual - part 1290

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-853

(2) Measure the voltage between terminal No. 42 and ground.

• Voltage should be battery positive voltage.

Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to Step 5.
NO :  Go to Step 3.

STEP 3. Measure the backup power supply voltage at PCM 
harness side connector B-20.

(1) Disconnect the PCM connector B-20 and measure at the 

harness side.

(2) Measure the voltage between terminal No. 42 and ground.

• Voltage should be battery positive voltage.

Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to Step 4.
NO :  Repair harness wire between battery and PCM 

connector B-20 (terminal No. 42) because of open 
circuit or short circuit to ground. Then go to Step 6.

25

21

24 23 22

29 28 27 26

34 33 32 31 30

38 37 36 35

43 42 41 40 39

AK203003AB

POWER PLANT ECU 
CHECK HARNESS 
CONNECTOR 

AK303092

25

21

24 23 22

29 28 27 26

34 33 32 31 30

38 37 36 35

43 42 41 40 39

CONNECTOR: B-20

B-20

PCM

AB

HARNESS CONNECTOR: 
COMPONENT SIDE

AIR CLEANER

25

21

24 23 22

29 28 27 26

34 33 32 31 30

38 37 36 35

43 42 41 40 39

AK303187

B-20 HARNESS 
CONNECTOR: 
COMPONENT SIDE

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-854

STEP 4. Check harness connector B-20 at PCM for 
damage.

Q: Is the harness connector in good condition?

YES : Repair harness wire between battery and PCM 

connector B-20 (terminal No. 42) because of harness 
damage. Then go to Step 6.

NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 6.

STEP 5. Check harness connector B-20 at PCM for 
damage.

Q: Is the harness connector in good condition?

YES : Replace the PCM. Then go to Step 6.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 6.

AK303092

25

21

24 23 22

29 28 27 26

34 33 32 31 30

38 37 36 35

43 42 41 40 39

CONNECTOR: B-20

B-20

PCM

AB

HARNESS CONNECTOR: 
COMPONENT SIDE

AIR CLEANER

AK303092

25

21

24 23 22

29 28 27 26

34 33 32 31 30

38 37 36 35

43 42 41 40 39

CONNECTOR: B-20

B-20

PCM

AB

HARNESS CONNECTOR: 
COMPONENT SIDE

AIR CLEANER

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-855

STEP 6. Using scan tool MB991958, read the diagnostic 
trouble code (DTC).

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) Read the DTC.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC P1603 set?

YES : Retry the troubleshooting.
NO :  The inspection is complete.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-856

DTC P2066: Fuel Level Sensor (sub) Circuit Range/Performance 

Fuel Level Sensor Circuit

AK302865

FUEL LEVEL
SENSOR (SUB)

FUEL LEVEL SENSOR (MAIN)
(INTEGRATED IN FUEL PUMP MODULE)

13

2

1

2

1

11

PINK-

BLA

CK

BLA

CK

PINK-
BLACK

PINK-

BLA

CK

PINK-

BLA

CK

24

GRA

Y

GRA

Y

POWERTRAIN 
CONTROL
MODULE (PCM) 

C-28

      D-18
(MU802058)

      D-17
(MU802004)

CONBINATION METER

1

2 3

4

5

     B-20

22

21

23 24 25

26 27 28 29

30 31 32 33 34

35 36 37 38

39 40 41 42 43

C-25

1

2

AK303156

CONNECTOR: D-17

AB

SERVICE
HOLE

FUEL LEVEL
SENSOR (SUB)

D-17

AK303157

SERVICE
HOLE

AB

FUEL PUMP MODULE
(INCORPORATING FUEL
LEVEL SENSOR (MAIN)
AND FUEL TANK
TEMPERATURE SENSOR)

CONNECTOR: D-18

D-18 (GR)