Mitsubishi Galant (2004+). Manual - part 1203

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-505

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• Engine is running.

Judgment Criteria

• Injector coil surge voltage (battery positive volt-

age + 2 volts) has not been detected for 2 sec-
onds.

.

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:)

• No.4 cylinder injector failed.

• Open or shorted No.4 cylinder injector circuit, 

harness damage, or connector damage.

• PCM failed.

START

END

NO

NO

NO

YES

YES

YES

MALFUNCTION

GOOD

MONITORING

CONDITIONS

CONTINUOUS

FAILURE FOR 2secs

INJ. SURGE V < V

B

 + 2.0 V

AK204052

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-506

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

• MB991658: Test Harness Set

• MB991923: Power Plant ECU Check Harness

STEP 1. Using scan tool MB991958, check actuator test 
item 04: No. 4 injector.

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) Start the engine and run at idle.

(3) Set scan tool MB991958 to the actuator testing mode for 

item 04, No. 4 injector.

(4) Warm up the engine to normal operating temperature: 80

°C 

to 95

°C (176°F to 203°F).

• The idle should become slightly rougher.

(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the actuator 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 the connector B-27 at No. 4 cylinder 
injector 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 10.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AK303110

M

1

2

CONNECTOR: B-27

B-27 (GR)

HARNESS CONNECTOR:
COMPONENT SIDE

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-507

STEP 3. Check the No. 4 cylinder injector.

(1) Disconnect the No.4 cylinder injector connector B-27.

(2) Measure the resistance between injector side connector 

terminal No. 1 and No. 2.

 Standard value: 10.5 

− 13.5 ohms [at 20°C (68°F)]

Q: Is the resistance between 10.5 and 13.5 ohms [at 20

°C 

(68

°F)]?

YES : Go to Step 4.
NO :  Replace the No. 4 cylinder injector. Then go to Step 

10.

STEP 4. Measure the power supply voltage at No. 4 
cylinder injector connector B-27.

(1) Disconnect connector B-27 and measure at the harness 

side.

(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal No. 1 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 6.
NO :  Go to Step 5.

AK303110

M

1

2

CONNECTOR: B-27

B-27 (GR)

HARNESS CONNECTOR:
COMPONENT SIDE

AB

AK000559

2

1

INJECTOR SIDE
CONNECTOR

AB

AK303110

M

1

2

CONNECTOR: B-27

B-27 (GR)

HARNESS CONNECTOR:
COMPONENT SIDE

AB

AK303111

1

2

B-27 HARNESS 
CONNECTOR: 
COMPONENT SIDE

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-508

STEP 5. Check harness connector B-17X at MFI relay for 
damage.

Q: Is the connector in good condition?

YES : Repair harness wire between MFI relay connector 

B-17X (terminal No. 4) and No. 4 cylinder injector 
connector B-27 (terminal No. 1) because of open 
circuit or short circuit to ground.

Then go to Step 10.

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

Connector Inspection 

P.00E-2

. Then go to Step 10.

1

2

3

4

AK303017

CONNECTOR: B-17X

FRONT OF VEHICLE

B-17X

AB

HARNESS
CONNECTOR:
COMPONENT SIDE

RELAY BOX