Mitsubishi Galant (2004+). Manual - part 1192

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-461

.

CIRCUIT OPERATION

• 5-volt voltage is applied to the fuel tank tempera-

ture sensor output terminal (terminal No. 3) from 
the PCM (terminal No. 41) via the resistor in the 
PCM.

• The fuel tank temperature sensor output voltage 

increases when the resistance increases and 
decreases when the resistance decreases. The 
ground terminal (terminal No. 1) is grounded to 
the vehicle body.

.

TECHNICAL DESCRIPTION

• The fuel tank temperature sensor converts the 

fuel tank temperature to a voltage.

• The PCM detects the fuel tank temperature with 

this output voltage.

.

DESCRIPTIONS OF MONITOR METHODS
Fuel tank temperature sensor output voltage is out of 

specified range.

.

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

• Intake air temperature sensor

.

AK303085

CONNECTOR: B-20

PCM

AB

AIR CLEANER

B-20

AK303086

CONNECTOR: C-25

C-25

AB

AK303087

SERVICE
HOLE

AB

FUEL PUMP MODULE
(INCORPORATING FUEL LEVEL
SENSOR (MAIN) AND FUEL
TANK TEMPERATURE SENSOR)

CONNECTOR: D-18

D-18 (GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-462

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• 2 seconds or more have passed since the engine 

starting sequence was completed.

Judgement Criteria

• Sensor output voltage has continued to be 4.6 

volts or higher for 2 seconds.

.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function 

− OBD-II Drive Cycle − 

Procedure 6 

− Other Monitor 

P.13B-5

.

.

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

• Fuel tank temperature sensor failed.

• Open fuel tank temperature sensor circuit, har-

ness damage, or connector damage.

• PCM failed. 

START

MONITORING

CONDITIONS

END

NO

NO

NO

YES

YES

YES

MALFUNCTION

GOOD

OUTPUT VOLTAGE

< 0.1V

CONTINUOUS

FAILURE FOR 2secs

OUTPUT VOLTAGE

> 4.6V

NO

YES

AK302403

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-463

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

• MB991923: Power Plant ECU Check Harness

STEP 1. Using scan tool MB991958, check data list item 
4A: Fuel Tank 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 

4A, Fuel Tank Temperature Sensor.

• Approximately the same as the ambient air temperature 

when the engine is cooled.

(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.

STEP 2. Check harness connector D-18 at the fuel tank 
temperature sensor for damage.

Q: Is the harness connector in good condition?

YES : Go to Step 3.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 11.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

1

2

3

4

5

AK303088

HARNESS
CONNECTOR:
COMPONENT SIDE

SERVICE
HOLE

AB

FUEL PUMP MODULE
(INCORPORATING FUEL LEVEL
SENSOR (MAIN) AND FUEL
TANK TEMPERATURE SENSOR)

CONNECTOR: D-18

D-18 (GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-464

STEP 3. Check the fuel tank temperature sensor.

(1) Disconnect the fuel tank temperature sensor connector 

D-18.

(2) Measure the resistance between terminal No. 1 and No. 3 

of the fuel tank temperature sensor.

Standard value:

0.5 

− 12.0 kΩ

Q: Is the measured resistance between 0.5 and 12.0 k

Ω?

YES : Go to Step 4.
NO :  Replace the fuel tank temperature sensor. Then go to 

Step 11.

STEP 4. Check the sensor supply voltage at fuel tank 
temperature sensor harness side connector D-18.

(1) Disconnect the connector D-18 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 between 4.5 and 4.9 volts.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage between 4.5 and 4.9 volts?

YES : Go to Step 8.
NO :  Go to Step 5.

1

2

3

4

5

AK303088

HARNESS
CONNECTOR:
COMPONENT SIDE

SERVICE
HOLE

AB

FUEL PUMP MODULE
(INCORPORATING FUEL LEVEL
SENSOR (MAIN) AND FUEL
TANK TEMPERATURE SENSOR)

CONNECTOR: D-18

D-18 (GR)

1

2 3

4

5

AK203165

FUEL TANK TEMPERATURE
SENSOR CONNECTOR

AB

1

2

3

4

5

AK303088

HARNESS
CONNECTOR:
COMPONENT SIDE

SERVICE
HOLE

AB

FUEL PUMP MODULE
(INCORPORATING FUEL LEVEL
SENSOR (MAIN) AND FUEL
TANK TEMPERATURE SENSOR)

CONNECTOR: D-18

D-18 (GR)

1

2

3

4

5

AK303091

D-18 HARNESS 
CONNECTOR: 
COMPONENT SIDE

AB