Mitsubishi Galant (2004+). Manual - part 1288

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-845

STEP 12. Check for harness damage between throttle 
actuator control motor relay connector B-14X (terminal No. 
4) and PCM connector B-23 (terminal No. 122).

Q: Is the harness wire in good condition?

YES : Go to Step 13.
NO :  Repair it. Then go to Step 14.

1

2

3

4

AK303175

CONNECTOR: B-14X

FRONT OF VEHICLE

B-14X

AB

HARNESS
CONNECTOR:
COMPONENT SIDE

RELAY BOX

127 126 125 124 123 122 121

133 132 131 130 129 128

140 139 138 137 136 135 134

146 145 144 143 142 141

153 152 151 150 149 148 147

AK303058

HARNESS CONNECTOR: 
COMPONENT SIDE

CONNECTOR: B-23

B-23

PCM

AB

AIR CLEANER

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-846

STEP 13. Using scan tool MB991502, read the diagnostic 
trouble code (DTC).

CAUTION

To prevent damage to scan tool MB991502, always turn the 
ignition switch to the "LOCK"(OFF) position before con-
necting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) After the DTC has been deleted, read the DTC again.
(4) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is DTC P0657 set?

YES : Replace the PCM. Then go to Step 14.
NO :  It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

P.00-6

.

STEP 14. Using scan tool MB991502, read the diagnostic 
trouble code (DTC).

(1) Connect scan tool MB991502 to the data link connector.
(2) Turn the ignition switch to the "ON" position.

(3) After the DTC has been deleted, read the DTC again.
(4) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is DTC P0657 set?

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

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-847

DTC P1601: Communication Malfunction (between PCM and Throttle Actuator Control Unit)

CAUTION

If DTC P1601 has been set, TCL related DTC 
U1120 is also set. After P1601 has been diag-
nosed, don't forget to erase DTC U1120.

.

TECHNICAL DESCRIPTION

• PCM checks the communication lines for abnor-

mal conditions.

.

DESCRIPTIONS OF MONITOR METHODS
Communication with throttle actuator control unit is 

impossible.

.

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

.

DTC SET CONDITIONS

Check Conditions

• Battery positive voltage is higher than 6.3 volts.

Judgement Criteria

• PCM detects an error in communication with the 

throttle actuator control unit for 0.05 second.

• Throttle actuator control module detects an error 

in communication with the PCM for 0.125 sec-
ond.

.

OBD-II DRIVE CYCLE PATTERN
None.

.

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

• PCM failed.

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-848

STEP 1. Using scan tool MB991958, read the diagnostic 
trouble code (DTC)

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) After the DTC has been deleted, read the DTC again.
(4) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is DTC P01601 set?

YES : Replace the PCM.
NO :  It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

P.00-6

.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827