Mitsubishi Eclipse. Manual - part 206

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-317

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• 60 seconds have elapsed from the start of the 

previous monitoring.

• Engine coolant temperature is higher than 20°C 

(68

°F).

• While the heated oxygen sensor (rear) heater is 

on.

• Battery positive voltage is at between 11 and 16.5 

volts.

Judgment Criteria

• Heater current of the heated oxygen sensor 

(rear) heater has continued to be lower than 0.16 
ampere or higher than 5.0 ampere for 4 seconds.

.

OBD-ll DRIVE CYCLE PATTERN
Refer to Diagnostic Function 

− OBD-ll Drive Cycle − 

Procedure 6 

− Other Monitor 

P.13A-5

.

.

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

• Open or shorted heated oxygen sensor (rear) 

heater circuit, or harness damage.

• Open circuit in heated oxygen sensor (rear) 

heater.

• Connector damage.

• ECM failed. <M/T>

• PCM failed. <A/T>

DIAGNOSIS

Required Special Tool:

• MB991658: Test Harness 

START

END

YES

YES

YES

YES

NO

NO

NO

NO

MALFUNCTION

GOOD

CONTINUOUS

FAILURE FOR 4secs

MONITORING

CONDITIONS

CURRENT < 0.16A

CURRENT > 5.0A

AK301443

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-318

STEP 1. Check connector C-23 at the heated oxygen 
sensor (rear) for damage.
Q: Is the 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.

AK300405

2

1

6 5 4 3

AB

C-23

HEATED OXYGEN
SENSOR (REAR)

CONNECTOR: C-23

HARNESS 
CONNECTOR:
HARNESS SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-319

STEP 2. Check the heated oxygen sensor (rear).
(1) Disconnect heated oxygen sensor (rear) connector C-23 

and connect test harness special tool, MB991658, to the 
connector on the heated oxygen (rear) sensor side.

(2) Measure the resistance between heated oxygen sensor 

connector terminal No. 5 and terminal No. 6.

Standard value: 11 

− 18 ohms [at 20°C (68°F)]

Q: Is the measured resistance between 11 and 18 ohms?

YES : Go to Step 3.
NO :  Replace the heated oxygen sensor (rear). Then go to 

Step 12.

AK300405

2

1

6 5 4 3

AB

C-23

HEATED OXYGEN
SENSOR (REAR)

CONNECTOR: C-23

HARNESS 
CONNECTOR:
HARNESS SIDE

AK000121AB

HEATED OXYGEN SENSOR
EQUIPMENT SIDE CONNECTOR

MB991658

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-320

STEP 3. Measure the power supply voltage at heated 
oxygen sensor (rear) harness side connector C-23.
(1) Disconnect the connector C-23 and measure at the harness 

side.

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

(3) Measure the voltage between terminal No. 3 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 harness 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 heated oxygen sensor 
(rear) connector C-23 (terminal No. 5) 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.

AK300405

2

1

6 5 4 3

AB

C-23

HEATED OXYGEN
SENSOR (REAR)

CONNECTOR: C-23

HARNESS 
CONNECTOR:
HARNESS SIDE

AK000322

AI

2

1

6 5 4 3

C-23 HARNESS 
CONNECTOR: 
COMPONENT SIDE

AK300454

2

1

3

4

CONNECTOR: A-18X

AB

A-18X

HARNESS CONNECTOR:
COMPONENT SIDE