Mitsubishi Galant (2004+). Manual - part 1315

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-953

STEP 2. 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) Read the ABS-DTC.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the ABS-DTC set?

YES : Refer to GROUP 35B, Anti-Lock Braking 

System-Diagnostic Trouble Code Chart 

P.35B-11

.

NO :  Go to Step 3.

STEP 3. 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) Read the combination meter-DTC.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC U1102 set?

YES : Go to Step 4.
NO :  Go to Step 5.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-954

STEP 4. 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 U1102 set?

YES : Replace the ABS-ECU. Then go to Step 6.
NO :  It can be assumed that this malfunction is intermittent 

of CAN bus line between PCM and ABS-ECU. Refer 
to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

P.00-6

.

STEP 5. 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 U1102 set?

YES : Replace the PCM. Then go to Step 6.
NO :  It can be assumed that this malfunction is intermittent 

of CAN bus line between PCM and ABS-ECU. Refer 
to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

P.00-6

.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-955

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 U1102 set?

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

DTC U1108: COMBINATION METER TIME-OUT

CAUTION

• If the PCM output the DTC U1102, make sure 

to diagnose the CAN bus line.

• Before replacing the ECU, make sure that the 

communication circuit is operating normally.

.

DESCRIPTIONS OF MONITOR METHODS
There is no data from combination meter for the 

specified time. (Meter also detect communication 
error with PCM.)

.

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)

• Not applicable

.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-956

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• Battery positive voltage is 10 volts or higher.

• Engine is not cranked, or at least 3 seconds have 

passed since engine was cranked.

Judgement Criteria

• Unable to receive combination meter signals 

through the CAN bus line.

.

COMMENT

Current Trouble

• Some of the possible causes are a harness or 

connector damage between the PCM and the 
combination meter on the CAN bus line, a failure 
in the combination meter power supply system, a 
failure in the combination meter, or a failure in the 
PCM.

Past Trouble

• Proceed to troubleshoot based on a harness or 

connector damage on the CAN bus line between 
the PCM and combination meter, and a failure in 
the combination meter power supply system. 
Refer to "How to cope with past trouble" (Refer to 
GROUP 00, How to Use Troubleshooting/Inspec-
tion Service Points 

P.00-6

).

NOTE: If a malfunction occurred in the past, a failure 
cannot be discovered through the MUT 

−

 III CAN bus 

diagnosis even if there might be a problem with the 
CAN bus. In this case, refer to GROUP 00, How to 
Use Troubleshooting/Inspection Service Points-How 
to Cope with Intermittent Malfunction 

P.00-6

. Fur-

thermore, it is possible to narrow down the areas of 
the possible failures from the DTCs that are output 
by the ECUs, which are communicating on the CAN 
bus (Refer to GROUP 54C, CAN bus line Diagnos-
tics Flow 

P.54C-6

).

.

START

END

NO

NO

YES

YES

YES

NO

MALFUNCTION

CONTINUOUS

FAILURE FOR 5secs

MONITORING

CONDITIONS

AK204025

COMMUNICATION STATUS

FAILS

GOOD