Mitsubishi Galant 9G. Manual - part 1202

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1108

AK303253

AK303253

CONNECTOR: C-208, C-210

AB

JUNCTION
BLOCK

C-210

C-208

FUEL PUMP
RELAY (1)

FUEL PUMP
RELAY (2)

AK303231

CONNECTOR: C-29

C-29

AB

AK303157

SERVICE
HOLE

AB

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

CONNECTOR: D-18

D-18 (GR)

AK303243

CONNECTOR: C-214

AB

JUNCTION
BLOCK

C-214

AK303147

CONNECTOR: B-19

PCM

AB

AIR CLEANER

B-19 (B)

AK303244

CONNECTOR: C-215

AB

JUNCTION
BLOCK

C-215

AK203191

CONNECTOR: C-308

C-308

AB

AK303227

CONNECTOR: C-211

C-211

AB

JUNCTION
BLOCK

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1109

.

CIRCUIT OPERATION

• Battery positive voltage is applied to the fuel 

pump relay 1 (terminal No. 3) from the ignition 
switch-IG.
Ground is provided through terminal No. 2 to 
chassis ground.

• When the ignition switch is turned to the "ON" 

position, the battery positive voltage is applied to 
the fuel pump relay 2 (terminal No. 1) from the 
fuel pump relay 1 (terminal No. 1).

• Battery positive voltage is applied to the fuel 

pump relay 2 (terminal No. 3) from the ignition 
switch-IG.

• During cranking and while the engine is running, 

the PCM turns the power transistor in the PCM 
ON to ground the fuel pump relay 2 coil. With this, 
the fuel pump relay turns ON, and the battery 
positive voltage is supplied to the fuel pump from 
the fuel pump relay 2 (terminal No. 4).

.

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

• Malfunction of the fuel pump relay.

• Malfunction of the fuel pump.

• Improper connector contact, open or short-circu-

lated harness wire.

• Malfunction of the PCM.

AK203254

CONNECTOR: C-204

C-204

AB

JUNCTION
BLOCK

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1110

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

STEP 1. Using scan tool MB991958, check actuator test 
item 07: Fuel Pump.

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 for item 

07, Fuel Pump.

• An operation sound of the fuel pump should be heard.

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

YES : That this malfunction is intermittent. Refer to GROUP 

00, How to Use Troubleshooting/Inspection Service 
Points 

− How to Cope with Intermittent Malfunctions 

P.00-14

.

NO :  Go to Step 2.

STEP 2. Check harness connector C-210 at fuel pump relay 
1 and harness connector C-208 at fuel pump relay 2 for 
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 3.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then confirm that the 

malfunction symptom is eliminated.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AK303255

3

4

1

2

3

4

1

2

CONNECTOR: C-208, C-210

AB

JUNCTION
BLOCK

C-210

C-208

HARNESS 
CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1111

STEP 3. Check the fuel pump relay 1 and 2.

CAUTION

Because it is not possible to distinguish the top and the 
bottom of the fuel pump relay, inspect it with the triangle 
mark printed on the relay facing upward.
(1) Remove the fuel pump relay 1 and 2.

(2) Check for continuity between the each fuel pump relay 

terminals No. 2 and No. 3.

• There should be continuity. (approximately 70 ohms)

(3) Use jumper wires to connect each fuel pump relay terminal 

No. 3 to the positive battery terminal and terminal No. 2 to 
the negative battery terminal.

(4) Check for continuity between the each fuel pump relay 

terminals No. 1 and No. 4 while connecting and 
disconnecting the jumper wire at the negative battery 
terminal.

• Should be less than 2 ohms. (Negative battery terminal 

connected)

• Should be open loop. (Negative battery terminal discon-

nected)

(5) Install the fuel pump relay 1 and 2.
Q: Is the measured resistance normal?

YES : Go to Step 4.
NO :  Replace the fuel pump relay 1 and/or 2. Then confirm 

that the malfunction symptom is eliminated.

AK303255

3

4

1

2

3

4

1

2

CONNECTOR: C-208, C-210

AB

JUNCTION
BLOCK

C-210

C-208

HARNESS 
CONNECTOR:
COMPONENT SIDE

AK104052

2

3 4

1

FUEL PUMP
RELAY SIDE
CONNECTOR

AB

AK104053

1 2
3 4

AB

FUEL PUMP
RELAY SIDE
CONNECTOR