Mitsubishi Galant (2004+). Manual - part 964

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-673

STEP 3. Measure the 5-volt reference signal at PCM 
connector B-20 by using check harness special tool 
MB991923.

(1) Disconnect all the connectors from the PCM.

(2) Connect special tool MB991923 (check harness) between 

the PCM and the body-side harness connector.

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

AC306248

B-20 HARNESS

CONNECTOR:

COMPONENT SIDE

AB

B-20

CONNECTOR: B-20

PCM

AIR
CLEANER

AC209793AJ

SPECIAL TOOL 23-PIN CONNECTOR
WITHOUT RED TAPE
(PCM CONNECTOR B-20)

B-20

PCM

MB991923

BODY SIDE
HARNESS

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-674

(4) Measure the voltage between terminal 21 and ground.

• The voltage should measure between 4.9 and 5.1 volts.

(5) 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 5.
NO :  Go to Step 4.

STEP 4. Check PCM connector B-20 for loose, corroded or 
damaged terminals, or terminals pushed back in the 
connector.

Q: Are the connector and terminals in good condition?

YES : Go to Step 16.
NO :  Repair or replace the faulty components (Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-2

). Then go to Step 17.

AC211192AB

SPECIAL TOOL 23-PIN
CONNECTOR
(WITHOUT RED TAPE):
COMPONENT SIDE

AC306248

B-20 HARNESS

CONNECTOR:

COMPONENT SIDE

AB

B-20

CONNECTOR: B-20

PCM

AIR
CLEANER

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-675

STEP 5. Measure the sensor output voltage at PCM 
connector B-20 by using check harness special tool 
MB991923. 

(1) Disconnect all the connectors from the PCM.

(2) Connect special tool MB991923 (check harness) between 

the PCM and the body-side harness connector.

(3) Turn the ignition switch to the "ON" position.
(4) Remove the fuel cap.

AC306248

B-20 HARNESS

CONNECTOR:

COMPONENT SIDE

AB

B-20

CONNECTOR: B-20

PCM

AIR
CLEANER

AC209793AJ

SPECIAL TOOL 23-PIN CONNECTOR
WITHOUT RED TAPE
(PCM CONNECTOR B-20)

B-20

PCM

MB991923

BODY SIDE
HARNESS

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-676

(5) Measure the voltage between terminal 22 and ground.

• The voltage should measure 0.5 volt or less.

(6) Install the fuel cap.
(7) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage 0.5 volt or less?

YES : Go to Step 6.
NO :  Go to Step 9.

STEP 6. Measure the signal voltage at intermediate 
connector D-23. 
(1) Remove the rear seat cushion assembly (Refer to GROUP 

52A, Rear Seat 

P.52A-30

).

(2) Remove the hole cover (RH).

(3) Disconnect fuel tank differential pressure sensor connector 

D-23.

(4) Use special tool MB991658 to connect terminals 1,2 and 3 

of  the fuel tank differential pressure sensor connector D-23.

(5) Turn the ignition switch to the "ON" position.
(6) Remove the fuel cap. 
(7) Measure the voltage between connector D-23 terminal 1 

and ground.

• The voltage should measure between 2.0 and 3.0 volts.

(8) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage between 2.0 and 3.0 volts?

YES : Go to Step 7.
NO :  Go to Step 15.

AC211193 AB

SPECIAL TOOL 23-PIN
CONNECTOR
(WITHOUT RED TAPE):
COMPONENT SIDE

AC306089

HOLE COVER

AB

AC305266

CONNECTOR: D-23

AB

D-23 (B)

AC306775

AB

MB991658

1 2 3

D-23 (B)