Mitsubishi Montero Sport (2004+). Manual - part 310

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-653

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• Vehicle speed has reached 1.5 km/h (0.93 mph) 

or more at least once.

• Under the closed loop idle speed control.

• Engine coolant temperature is higher than 77°C 

(171

°F).

• Battery positive voltage is higher than 10 volts.

• Barometric pressure is higher than 76 kPa (22.4 

in.Hg).

• Intake air temperature is higher than −10°C 

(14

°F).

• 60 seconds have elapsed from the start of the 

previous monitoring.

• Target idle air control motor position is 0 steps.

Judgment Criteria

• Actual idle speed has continued to be higher than 

the target idle speed by 200 r/min (300 r/min*) or 
more for 12 seconds.

*: Specs in parentheses are applicable if the max-

imum air temperature during the previous 
operation was more than 45

°C (113°F).

.

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:)

• Idle air control motor failed.

• Open or shorted idle air control motor circuit, har-

ness damage or connector damage.

• Intake system vacuum leaks.

• PCM failed.

END

NO

NO

NO

YES

YES

YES

MALFUNCTION

GOOD

START

CALCULATE  

Ne

MONITORING

CONDITIONS

Ne = (ACTUAL-Ne) - (TARGET-Ne)

Ne: ENGINE SPEED

  

Ne < -100 r/min OR

> 200 r/min

HAVE 10secs PASSED?

AK204002

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-654

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I

• MB991827: USB Cable

• MB991911: Main Harness B

• MB991709: Test Harness

STEP 1. Using scan tool MB991958, read the diagnostic 
trouble code (DTC).

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, read the DTC.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC other than P0507 set?

YES : Refer to Diagnostic Trouble Code Chart 

P.13A-26

.

NO :  Go to Step 2.

STEP 2. Check for intake system vacuum leaks.
Q: Are there any abnormalities?

YES : Go to Step 3.
NO :  Repair or replace it. Then go to Step 14.

STEP 3. Check connector A-40 at idle air control motor for 
damage.
Q: Is the connector in good condition?

YES : Go to Step 4.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 14.

AK303629AB

MB991911

MB991827

MB991824 

16-PIN

AK200476

1

2

3

4

5

6

AB

CONNECTOR: A-40

A-40(B)

HARNESS 
CONNECTOR: 
COMPONENT 
SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-655

STEP 4. Check the idle air control motor coil resistance.
(1) Disconnect the idle air control motor connector A-40.
(2) Measure the resistance between idle air control motor 

connector terminal No. 2 and either terminal No. 1 or 
terminal No. 3.

Standard value: 28 

− 33 ohms [at 20° C (68° F)]

(3) Measure the resistance between idle air control motor 

connector terminal No. 5 and either terminal No. 4 or 
terminal No. 6.

Standard value: 28 

− 33 ohms [at 20° C (68° F)]

Q: Is the measured resistance between 28 and 33 ohms [at 

20

° C (68° F)]?

YES : Go to Step 5.
NO :  Replace the idle air control motor. Then go to Step 14.

AK200476

1

2

3

4

5

6

AB

CONNECTOR: A-40

A-40(B)

HARNESS 
CONNECTOR: 
COMPONENT 
SIDE

AKX01561

1 2 3
4 5 6

1 2 3
4 5 6

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-656

STEP 5. Measure the power supply voltage at idle air 
control motor harness side connector A-40.
(1) Disconnect the connector A-40 and measure at the harness 

side.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminals No. 2, No. 5 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 7.
NO :  Go to Step 6.

STEP 6. Check connector C-59 at MFI relay for damage.
Q: Is the connector in good condition?

YES : Check connector C-14 at intermediate connector for 

damage, and repair or replace as required. Refer to 
GROUP 00E, Harness Connector Inspection 

P.00E-2

. If intermediate connectors is in good 

condition, repair harness wire between MFI relay 
connector C-59 (terminal No. 1) and idle air control 
motor connector A-40 (terminals No. 2, No. 5) 
because of open circuit or short circuit to ground. 
Then go to Step 14.

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

Connector Inspection 

P.00E-2

. Then go to Step 14.

AK200476

1

2

3

4

5

6

AB

CONNECTOR: A-40

A-40(B)

HARNESS 
CONNECTOR: 
COMPONENT 
SIDE

AKX01428

3 2 1

A-40 HARNESS 
CONNECTOR: 
COMPONENT SIDE

AN

6 5 4

AK200023

2 1

3

4

CONNECTOR: C-59

AB

C-59

HARNESS 
CONNECTOR:
COMPONENT 
SIDE