Mitsubishi Eclipse. Manual - part 622

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-1031

AK300096

D-17 (GR)

FUEL PUMP
MODULE

AB

CONNECTOR: D-17

AK300244

CONNECTOR: C-52 <A/T>

AC

PCM

C-52 (GR)

AK300091

CONNECTOR: C-51 <M/T>

ECM

AF

C-51 (GR)

AK300116

CONNECTOR: C-87

AB

C-87

AK300100

CONNECTOR: C-101

AB

C-101

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

AK300127

CONNECTORS: C-105, 107

FUEL PUMP
RELAY (2)

JUNCTION BLOCK

AB

FUEL PUMP
RELAY (1)

C-105

C-107

AK300123

CONNECTOR: C-108

AB

C-108

AK300124

CONNECTOR: C-111

AB

C-111

AK300125

CONNECTOR: C-112

AB

C-112

AK300118

CONNECTOR: C-89

AC

C-89

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-1032

.

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 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).

• A battery positive voltage is applied on the fuel 

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

• During cranking and while the engine is running, 

the ECM <M/T> or PCM <A/T> turns the power 
transistor in the ECM <M/T> or PCM <A/T> 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 1 and 2.

• Malfunction of the fuel pump.

• Improper connector contact, open or 

short-circuited harness wire.

• Malfunction of the ECM <M/T> or PCM <A/T>.

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

AK300119

CONNECTOR: C-28

AB

C-28

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-1033

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 

P.00-6

. 

NO :  Go to Step 2.

STEP 2. Check connector C-107 at fuel pump relay 1 and 
connector C-105 at fuel pump relay 2 for damage.
Q: Is the 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.

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

AK300456

2 1

3

4

2 1

3

4

CONNECTORS: C-105, 107

C-105

C-107

AB

C-107 HARNESS CONNECTOR:
COMPONENT SIDE

C-105 HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-1034

STEP 3. Check the fuel pump relay 1 and 2.
(1) Remove the fuel pump relay 1 and 2.

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

terminals 2 and 3.

• There should be continuity. (approximately 70 Ω)

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

3 to the positive battery terminal and terminal 2 to the 
negative battery terminal.

(4) Check the 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 ohm. (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 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.

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

3

4

1

2

AK300456

2 1

3

4

2 1

3

4

CONNECTORS: C-105, 107

C-105

C-107

AB

C-107 HARNESS CONNECTOR:
COMPONENT SIDE

C-105 HARNESS CONNECTOR:
COMPONENT SIDE

AK103837

2

3 4

1

FUEL PUMP
RELAY SIDE
CONNECTOR

AB

AK103838

1 2
3 4

1 2
3 4

FUEL PUMP
RELAY SIDE
CONNECTOR

AB