Mitsubishi 380. Manual - part 494

MULTIPOINT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPOINT FUEL INJECTION (MPI)

13A-68

STEP 5. Measure the power supply voltage at ENGINE-ECU 
connector B-20 by using  ENGINE-ECU check harness 
special tool MB992044.
(1) Disconnect the all ENGINE-ECU connectors and connect  

ENGINE-ECU check harness special tool MB992044 
between the separated connectors.

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

(3) Measure the voltage between terminal No. 33 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 8.
NO :  Go to Step 6.

STEP 6. Check harness connector B-20 at ENGINE-ECU for 
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 7.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 11. 

16DB400A

COVER

ENGINE

CONTROL

UNIT

AIR

CLEANER

03DB215A

B-20 HARNESS 

CONNECTOR 

16DB400A

COVER

ENGINE

CONTROL

UNIT

AIR

CLEANER

MULTIPOINT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPOINT FUEL INJECTION (MPI)

13A-69

STEP 7. Check for open circuit or short circuit to ground 
between left bank heated oxygen sensor (rear) connector 
B-24 (terminal No. 3) and ENGINE-ECU connector B-20 
(terminal No. 33).
Q: Is the harness wire in good condition?

YES : Then go to Step 8.
NO :  Repair it. Then go to Step 11.

16DB400A

COVER

ENGINE

CONTROL

UNIT

AIR

CLEANER

1

2

3

4

AK303079

HARNESS

CONNECTOR:

COMPONENT SIDE

CONNECTOR: B-24

AB

LEFT BANK

HEATED OXYGEN

SENSOR (REAR)

B-24 (GR)

MULTIPOINT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPOINT FUEL INJECTION (MPI)

13A-70

STEP 8. Check harness connector B-20 at ENGINE-ECU for 
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 9.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 11. 

16DB400A

COVER

ENGINE

CONTROL

UNIT

AIR

CLEANER

MULTIPOINT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPOINT FUEL INJECTION (MPI)

13A-71

STEP 9. Check for harness damage between MPI relay 
connector B-17X (terminal No. 4) and left bank heated 
oxygen sensor (rear) connector B-24 (terminal No. 4).
Q: Is the harness wire in good condition?

YES : Go to Step 10.
NO :  Repair it. Then go to Step 11.

1

2

3

4

AK303017

CONNECTOR: B-17X

FRONT OF VEHICLE

B-17X

AB

HARNESS

CONNECTOR:

COMPONENT SIDE

RELAY BOX

1

2

3

4

AK303079

HARNESS

CONNECTOR:

COMPONENT SIDE

CONNECTOR: B-24

AB

LEFT BANK

HEATED OXYGEN

SENSOR (REAR)

B-24 (GR)