Mitsubishi Eclipse. Manual - part 460

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-383

DIAGNOSIS

Required Special Tool:

• MB998464: Test Harness

STEP 1. Check connector B-24 at the left bank heated 
oxygen sensor (front) for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 2.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 12.

AK300424

1

2

3

4

LEFT BANK 
HEATED OXYGEN
SENSOR (FRONT)

CONNECTOR: B-24

AB

B-24 (B)

HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-384

STEP 2. Check the left bank heated oxygen sensor (front).
(1) Disconnect left bank heated oxygen sensor (front) 

connector B-24 and connect test harness special tool, 
MD998464, to the connector on the left bank heated oxygen 
(front) sensor side.

(2) Measure the resistance between heated oxygen sensor 

connector terminal 1 (red clip) and terminal 3 (blue clip).

Standard value: 4.5 

− 8.0 ohms [at 20°C (68°F)]

Q: Is the measured resistance between 4.5 and 8.0 ohms?

YES : Go to Step 3.
NO :  Replace the left bank heated oxygen sensor (front). 

Then go to Step 12.

AK300424

1

2

3

4

LEFT BANK 
HEATED OXYGEN
SENSOR (FRONT)

CONNECTOR: B-24

AB

B-24 (B)

HARNESS CONNECTOR:
COMPONENT SIDE

AKX01624

HEATED
OXYGEN
SENSOR
EQUIPMENT
SIDE
CONNECTOR

MD998464

BLUE

RED

AC

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-385

STEP 3. Check the power supply voltage at left bank 
heated oxygen sensor (front) harness side connector B-24.
(1) Disconnect the connector B-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 battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to Step 5.
NO :  Go to Step 4.

STEP 4. Check connector A-18X at the MFI relay for 
damage.
Q: Is the connector in good condition?

YES : Repair harness wire between MFI relay connector 

A-18X (terminal No. 4) and left bank heated oxygen 
sensor (front) connector B-24 (terminal No. 1) 
because of open circuit or short circuit to ground. 
Then go to Step 12.

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

Connector Inspection 

P.00E-2

. Then go to Step 12.

AK300424

1

2

3

4

LEFT BANK 
HEATED OXYGEN
SENSOR (FRONT)

CONNECTOR: B-24

AB

B-24 (B)

HARNESS CONNECTOR:
COMPONENT SIDE

AKX01498

2

1

4

3

B-24 HERNESS 
CONNECTOR: 
COMPONENT SIDE

AV

AK300454

2

1

3

4

CONNECTOR: A-18X

AB

A-18X

HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-386

STEP 5. Check the power supply voltage at ECM connector 
C-51 <M/T> or PCM connector C-52 <A/T> by backprobing.
(1) Do not disconnect the connector C-51 <M/T> or C-52 

<A/T>.

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

(3) Measure the voltage between terminal 3 and ground by 

backprobing.

• Voltage should be battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to Step 8.
NO :  Go to Step 6.

AK300458

2

3

4

5

6

7

8

9

11

12

13

14

15

16

17

18

19

20

30

21

22

23

24

25

26

27

28

29

31

32

33

34

35

1

10

CONNECTOR: C-52 <A/T>

C-52 (GR)

AB

HARNESS CONNECTOR:
COMPONENT SIDE

AK300443

2

3

4

5

6

7

8

9

11

12

13

14

15

16

17

18

19

20

30

21

22

23

24

25

26

27

28

29

31

32

33

34

35

1

10

CONNECTOR: C-51 <M/T>

C-51 (GR)

AB

HARNESS CONNECTOR:
COMPONENT SIDE

AKX01540

AKX01540

1

2

3 4

5 6

7 8

10 11 12 13 14 15 16 17 18 19 20 21 22 23

24 25

26 27 28 29

30 31 32 33

34 35

C-51<M/T>, C-52<A/T>
HARNESS CONNECTOR:
HARNESS SIDE 

AI

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