Mitsubishi Montero Sport (2004+). Manual - part 213

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-265

.

CIRCUIT OPERATION

• Power is supplied from the MFI relay (terminal 

No. 1) to the right bank heated oxygen sensor 
(rear) heater.

• The PCM (terminal No. 27) controls continuity to 

the right bank heated oxygen sensor (rear) 
heater by turning the power transistor in the PCM 
"ON" and "OFF".

.

BACKGROUND

• The PCM checks whether the heater current is 

within a specified range when the heater is ener-
gized.

.

DESCRIPTIONS OF MONITOR METHODS
Right bank heated oxygen sensor heater (rear) cur-

rent is out of specified range when engine coolant 
temperature is over 20

°C (68°F).

.

MONITOR EXECUTION
Continuous

.

MONITOR EXECUTION CONDITIONS (Other 
monitor and Sensor)

Other Monitor (There is no temporary DTC stored 

in memory for the item monitored below)

• Not applicable

Sensor (The sensor below is determined to be 

normal)

• Engine coolant temperature sensor

.

AK200018 AC

CONNECTOR: E-45

E-45(B)

AK201000

MFI RELAY

CONNECTOR: C-59

AB

C-59

AK103738AD

CONNECTOR: C-89

PCM

C-89(GR)

AK200491

E-47(GR)

AB

CONNECTOR: E-47

RIGHT BANK
HEATED OXYGEN
SENSOR (REAR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-266

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 right bank heated oxygen sensor (rear) 

heater is on.

• Battery positive voltage is at between 11 and 16.5 

volts.

Judgment Criteria

• Right bank heater current of the right bank 

heated oxygen sensor (rear) heater has contin-
ued to be lower than 0.16 ampere or higher than 
5.0 ampere for 4 seconds.

.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function 

− OBD-II Drive Cycle − 

Procedure 6 

− Other Monitor 

P.13A-4

.

.

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

• Open or shorted right bank heated oxygen sen-

sor (rear) heater circuit, or harness damage.

• Open circuit in right bank heated oxygen sensor 

(rear) heater, or harness damage.

• Right bank heated oxygen sensor (rear) failed.

• Connector damage.

• PCM failed.

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)

13A-267

DIAGNOSIS

Required Special Tool:

• MB991316: Test Harness

STEP 1. Check connector E-47 at the right bank 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.

AK200492

1

2

3

4

E-47(GR)

AB

CONNECTOR: E-47

HARNESS 
CONNECTOR: 
COMPONENT SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (REAR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-268

STEP 2. Check the right bank heated oxygen sensor (rear).

(1) Disconnect right bank heated oxygen sensor (rear) 

connector E-47 and connect test harness special tool, 
MB991316, to the connector on the right bank heated 
oxygen (rear) sensor side.

(2) Measure the resistance between heated oxygen sensor 

connector terminal No. 1 (red clip) and terminal No. 3 (blue 
clip).

Standard value: 11 

− 18 ohms [at 20°C (68°F)]

Q: Is the measured resistance between 11 and 18 ohms [at 

20

°C (68°F)]?

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

Then go to Step 12.

AK200492

1

2

3

4

E-47(GR)

AB

CONNECTOR: E-47

HARNESS 
CONNECTOR: 
COMPONENT SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (REAR)

AKX01624 AB

MB991316

HEATED
OXYGEN
SENSOR
EQUIPMENT
SIDE
CONNECTOR

BLUE

RED