Mitsubishi Galant (2004+). Manual - part 840

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-177

DTC SET CONDITIONS <Range/Performance problem 

− low input (Time to reach closed loop 

temperature)>

Logic Flow Chart

Check Conditions, Judgement Criteria

• About 60 − 300 seconds have passed for the 

engine coolant temperature to rise to about 7

°C 

(45

°F) after starting sequence was completed.

• However, time is not counted when fuel is shut 

off.

.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function 

− OBD-II Drive Cycle − 

Procedure 6 

− Other Monitor 

P.13A-5

.

TROUBLESHOOTING HINTS (The most likely 

causes for this code to be set are:)

• Engine coolant temperature sensor failed.

• Harness damage in engine coolant temperature 

sensor circuit or connector damage.

• PCM failed.

START

END

YES

NO

NO

YES

MALFUNCTION

GOOD

TIME HAVE PASSED

AFTER STARTING?*

ENGINE
COOLANT
TEMP.

TEMP. 
WHERE
CLOSED LOOP
STARTS

>

MONITORING

CONDITIONS?

NO

YES

*: SEE DTC SET CONDITIONS-SET CONDITIONS, JUDGMENT CRITERIA

AK302018

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-178

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

STEP 1. Using scan tool MB991958, check data list item 21: 
Engine Coolant Temperature Sensor.

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 to the data reading mode for item 

21, Engine Coolant Temperature Sensor.

• The engine coolant temperature and temperature 

shown with the scan tool should approximately match.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

P.00-6

.

NO :  Go to Step 2.

AK303804AB

MB991910

DATA LINK
CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-179

STEP 2. Measure the sensor output voltage at engine 
coolant temperature sensor connector B-104 by 
backprobing.
(1) Do not disconnect the connector B-104.
(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal No. 1 and ground by 

backprobing.

• When engine coolant temperature is −20°C (−4°F), volt-

age should be between 3.9 and 4.5 volts.

• When engine coolant temperature is 0°C (32°F), voltage 

should be between 3.2 and 3.8 volts.

• When engine coolant temperature is 20°C (68°F), volt-

age should be between 2.3 and 2.9 volts.

• When engine coolant temperature is 40°C (104°F), volt-

age should be between 1.3 and 1.9 volts.

• When engine coolant temperature is 60°C (140°F), volt-

age should be between 0.7 and 1.3 volts.

• When engine coolant temperature is 80°C (176°F), volt-

age should be between 0.3 and 0.9 volt.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage within the specified range?

YES : Go to Step 3.
NO :  Go to Step 5.

STEP 3. Check harness connector B-104 at the engine 
coolant temperature sensor for damage.
Q: Is the harness 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.

AK303815

1

2

AB

CONNECTOR: B-104

B-104 (B)

HARNESS 
CONNECTOR:
COMPONENT SIDE

AK201572

2

1

AD

B-104 HARNESS 
CONNECTOR: 
HARNESS SIDE

AK303815

1

2

AB

CONNECTOR: B-104

B-104 (B)

HARNESS 
CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-180

STEP 4. Using scan tool MB991958, check data list item 21: 
Engine Coolant Temperature Sensor.

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 to the data reading mode for item 

21, Engine Coolant Temperature Sensor.

• The engine coolant temperature and temperature 

shown with the scan tool should approximately match.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

P.00-6

.

NO :  Replace the PCM. Then go to Step 14.

STEP 5. Check harness connector B-104 at engine coolant 
temperature sensor for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 6.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 14.

AK303804AB

MB991910

DATA LINK
CONNECTOR

MB991824

MB991827

AK303815

1

2

AB

CONNECTOR: B-104

B-104 (B)

HARNESS 
CONNECTOR:
COMPONENT SIDE