Mitsubishi Galant (2004+). Manual - part 1300

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-893

STEP 3. Measure the sensor supply voltage at accelerator 
pedal position sensor harness side connector C-24.

(1) Disconnect the connector C-24 and measure at the harness 

side.

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

(3) Measure the voltage between terminal No. 1 and ground.

• Voltage should be between 4.9 and 5.1 volts.

(4) Turn the ignition switch to the "LOCK"(OFF) position.
Q:  Is the measured voltage between 4.9 and 5.1 volts?

YES : Go to Step 7.
NO :  Go to Step 4.

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

Q: Is the harness connector in good condition?

YES : Go to Step 5.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 11.

AK303202

1

6 5 4 3 2

ACCELERATOR
PERAL

AB

CONNECTOR: C-24

C-24 (B)

ACCELERATOR 
PEDAL POSITION 
SENSOR

HARNESS
CONNECTOR:
COMPONENT SIDE

1

6 5 4 3 2

AK303203

C-24 HARNESS 
CONNECTOR: 
COMPONENT SIDE

AB

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-894

STEP 5. Check for open circuit and short circuit to ground 
between accelerator pedal position sensor connector C-24 
(terminal No. 1) and PCM connector B-20 (terminal No. 30).

Q: Is the harness wire in good condition?

YES : Go to Step 6.
NO :  Repair it. Then go to Step 11.

AK303202

1

6 5 4 3 2

ACCELERATOR
PERAL

AB

CONNECTOR: C-24

C-24 (B)

ACCELERATOR 
PEDAL POSITION 
SENSOR

HARNESS
CONNECTOR:
COMPONENT SIDE

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-895

STEP 6. Using scan tool MB991958, check data list item 78: 
Accelerator Pedal Position Sensor (main).

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 data reading mode for item 

78, Accelerator Pedal Position Sensor (main).

• Output voltage is between 0.7 and 1.3 volts when foot is 

released from accelerator pedal.

• Output voltage is 4.0 volts or higher when accelerator 

pedal is fully depressed.

(4) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is the sensor operating properly?

YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection. Service Points 

P.00-6

.

NO :  Replace the PCM. Then go to Step 11.

STEP 7. Check harness connector B-20 at PCM for 
damage.

Q: Is the harness connector in good condition?

YES : Go to Step 8.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 11.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

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-896

STEP 8. Check for harness damage between accelerator 
pedal position sensor connector C-24 (terminal No. 1) and 
PCM connector B-20 (terminal No. 30).

Q: Is the harness wire in good condition?

YES : Go to Step 9.
NO :  Repair it. Then go to Step 11.

AK303202

1

6 5 4 3 2

ACCELERATOR
PERAL

AB

CONNECTOR: C-24

C-24 (B)

ACCELERATOR 
PEDAL POSITION 
SENSOR

HARNESS
CONNECTOR:
COMPONENT SIDE

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