Mitsubishi Galant 9G. Manual - part 1037

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-448

STEP 8. Replace the left bank injector.
(1) Replace the left bank injector.
(2) Carry out a test drive with the drive cycle pattern. Refer to 

Diagnostic Function 

− OBD-II Drive Cycle − Procedure 2 − 

Fuel Trim Monitor 

P.13B-6

.

(3) Check the diagnostic trouble code (DTC).
Q: Is DTC P0175 set?

YES : Replace the PCM. Then go to Step 9.
NO :  The inspection is complete.

STEP 9. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to 

Diagnostic Function 

− OBD-II Drive Cycle − Procedure 2 − 

Fuel Trim Monitor 

P.13B-6

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0175 output?

YES : Retry the troubleshooting.
NO :  The inspection is complete.

AK303075

M

1

2

CONNECTOR: B-26, B-27, B-30

B-30 (GR)

B-27 (GR)

B-26 (GR)

HARNESS CONNECTOR:
COMPONENT SIDE

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-449

DTC P0181: Fuel Tank Temperature Sensor Circuit Range/Performance

1

2 3

4

5

22

21

23 24 25

26 27 28 29

30 31 32 33 34

35 36 37 38

39 40 41 42 43

AK400883

POWERTRAIN CONTROL
MODULE (PCM)

Fuel Tank Temperature  Sensor  Circuit

7

3

2

1

BLA

C

K

D-18

(MU802058)

41

FUEL TANK TEMPERATURE SENSOR
(INTEGRATED IN FUEL PUMP MODULE)

C-25

5 V

GRA

Y

-

GREEN

GRA

Y

-

GREEN

B-20

1 2

3 4

6

5

7 8

15 16

14

13

11 12

10

9

FROM PCM

AK303085

CONNECTOR: B-20

PCM

AB

AIR CLEANER

B-20

AK303086

CONNECTOR: C-25

C-25

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-450

.

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 at engine start is higher than 

engine coolant temperature at engine start by 
specified value when engine is cold start condi-
tion.

.

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

.

AK303839AB

CONNECTOR: D-18

SERVICE
HOLE

 FUEL TANK TEMPERATURE SENSOR
(INTEGRATED IN FUEL  PUMP MODULE)

D-18 (GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-451

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• The engine coolant temperature − intake air tem-

perature is 5

°C (9°F) or less when the engine is 

started.

• The engine coolant temperature is between 

−10°C (14°F) and 36°C (97°F) when the engine is 

started.

• The engine coolant temperature is higher than 

60

°C (140°F).

• Maximum vehicle speed is higher than 30 km/h 

(19 mph) after the engine starting sequence has 
been completed.

START

NO

YES

YES

YES

YES

NO

NO

NO

END

NO

YES

YES

NO

MALFUNCTION

GOOD

MONITORING

CONDITIONS

“FUEL TEMP. AT 

ENGINE START” -

“ENGINE COOLANT TEMP. AT 

ENGINE START”

> 15˚C (59˚F)

ENGINE

COOLANT TEMP.

> =60˚C (140˚F)

ENGINE

COOLANT TEMP.

> =60˚C (140˚F)

MAX.

VEHICLE SPEED

> 30km/h (19mph)

MAX.

VEHICLE SPEED

> 30km/h (19mph)

AK401537