Mitsubishi Galant 9G. Manual - part 1178

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1012

STEP 6. Using scan tool MB991958, read the diagnostic 
trouble code (DTC).
(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) After the MFI-DTC has been deleted, read the MFI-DTC 

again.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC U1110 set?

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

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1013

SYMPTOM PROCEDURES

INSPECTION PROCEDURE 1: Communication with Scan Tool Is Not Possible. (Comunication with All 
Systems Is Not Possible.)

AK400834

RED-BLA

CK

BLA

CK

RED

BLA

CK

12

1

5

16

C-125

MU803797

C-211

DATA LINK
CONNECTOR

4

JUNCTION
BLOCK

FUSIBLE
LINK (1)

1

C-216

MU801403

Data Link Connector Circuit

10

15A

1

6

4 5

11

10

1213

15

17

16

14

19

18

8 9

7

20

2 3

2122 23 2425 26 27 28

AK303209AB

CONNECTOR: C-125

DATA LINK 
CONNECTOR

C-125

ACCELERATOR
PEDAL

AK303210

CONNECTOR: C-216

C-216

AB

JUNCTION
BLOCK

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1014

.

CIRCUIT OPERATION

• A battery positive voltage is applied on the data 

link connector power terminal (terminal No. 16). 
The ground terminals (terminal No. 4, No. 5) are 
grounded to the vehicle body.

.

COMMENT

• The cause is probably a defect in power supply 

system (including ground) for the on-board diag-
nostic test mode line.

.

TROUBLESHOOTING HINTS (The most 
likely causes for this case:) 

• Malfunction of the data link connector.

• Damaged harness wire.

DIAGNOSIS

STEP 1. Measure the power supply voltage at data link 
connector C-125.
(1) Measure voltage between terminal No. 16 and ground.

• Voltage should be battery positive voltage.

Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to step 2.
NO :  Check harness connectors C-211, C-216 and C-29 at 

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

P.00E-2

. If intermediate 

connector C-211, C-216 and C-29 are in good 
condition, repair an open circuit between fusible link 
(1) and data link connector C-125 (terminal No. 16). 
Then confirm that the malfunction symptom is 
eliminated.

AK303227

CONNECTOR: C-211

C-211

AB

JUNCTION
BLOCK

AK303231

CONNECTOR: C-29

C-29

AB

AK303228

1 2 3 4 5 6

12

11

10

1516

14

13

9

7 8

AB

CONNECTOR: C-125

DATA LINK 
CONNECTOR

C-125

ACCELERATOR
PEDAL

HARNESS
CONNECTOR:
COMPONENT SIDE

AK303229

1 2 3 4 5 6 7 8

16

15

14

13

12

11

10

9

C-125 HARNESS 
CONNECTOR: 
COMPONENT SIDE

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-1015

STEP 2. Check the continuity at data link connector C-125.
(1) Check for the continuity between terminal No. 4, No. 5 and 

ground.

• Should be less than 2 ohms.

Q: Does continuity exist?

YES : Replace the scan tool. Then confirm that the 

malfunction symptom is eliminated.

NO :  Repair an open circuit or harness damage between 

data link connector C-125 (terminal No. 4, No. 5) and 
ground. Then confirm that the malfunction symptom is 
eliminated.

AK303228

1 2 3 4 5 6

12

11

10

1516

14

13

9

7 8

AB

CONNECTOR: C-125

DATA LINK 
CONNECTOR

C-125

ACCELERATOR
PEDAL

HARNESS
CONNECTOR:
COMPONENT SIDE

AK303230

1 2 3 4 5 6 7 8

16

15

14

13

12

11

10

9

D-125 HARNESS 
CONNECTOR: 
COMPONENT SIDE

AB