Mitsubishi Galant (2004+). Manual - part 1233

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-625

DTC P0403: Exhaust Gas Reculation Control Circuit

RED-

WHITE

RED-

WHITE

RED

RED-BLA

CK

RED-

WHITE

RED-

WHITE

BR

O

WN-WHITE

GRA

Y

-BLUE

BLA

CK-YELLO

W

AK302860

MFI RELAY

BATTERY

1

2

4

3

B-17X

B-105

(MU802056)

5

2

142

136

130

124

1

3

4

6

EXHAUST GAS
RECIRCULATION (EGR)
VALVE

POWERTRAIN
CONTROL
MODULE (PCM)

EGR Valve Circuit

1

2 3

4

5 6

B-23

RED-

WHITE

1

2

3

4

121 122 123 124 125 126 127

128 129 130 131 132 133

134 135 136 137 138 139 140

141 142 143 144 145 146

147 148 149 150 151 152 153

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-626

.

CIRCUIT OPERATION

• The EGR valve power is supplied from the MFI 

relay (terminal No. 4).

• The PCM (terminals No. 124, No. 130, No. 136, 

No. 142) drives the stepper motor by sequentially 
turning "ON" the power transistors in the PCM 
and providing ground to the idle air control motor 
(terminal No. 1, No. 3, No. 4, No. 6).

.

TECHNICAL DESCRIPTION

• To judge if there is open circuit in the EGR valve 

(stepper motor) drive circuit, PCM measure the 
surge voltage of the EGR valve motor coil.

.

DESCRIPTIONS OF MONITOR METHODS
Off-surge does not occur after stepper motor is oper-

ated on to off.

.

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)

• EGR stepper motor monitor

Sensor (The sensor below is determined to be 

normal)

• Mass airflow sensor

• Engine coolant temperature sensor

• Intake air temperature sensor

• Barometric pressure sensor

• Throttle position sensor

• Manifold absolute pressure sensor

• Accelerator position sensor

.

AK303136AB

B-105(GR)

CONNECTOR: B-105

EGR 
VALVE

BRAKE FLUID
RESERVOIR

AK303059

CONNECTOR: B-23

PCM

AB

AIR CLEANER

B-23

1

2

3

4

1

2

3

4

1

2

3

4

1

2

3

4

AK303014

CONNECTOR: B-17X

MFI RELAY

MFI RELAY

FRONT OF VEHICLE

B-17X

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-627

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• Battery positive voltage is higher than 10.3 volts.

• In a few seconds, just after ignition switch is 

turned to the "ON" position from the 
"LOCK"(OFF) position. (While EGR valve is ini-
tialized.)

Judgment Criteria

• The EGR valve motor coil surge voltage (battery 

positive voltage +2 volts) is not detected for 3 
seconds.

Check Conditions

• Battery positive voltage is higher than 10.3 volts.

• EGR valve is in operation after the engine start-

ing process is complete.

Judgment Criteria

• The EGR valve motor coil surge voltage (battery 

positive voltage +2 volts) is not detected for 30 
seconds.

.

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: )

• EGR valve (stepper motor) failed.

• Open or shorted EGR valve (stepper motor) cir-

cuit, harness damage or connector damage.

• PCM failed.

START

END

MALFUNCTION

GOOD

MONITORING

CONDITIONS

WAS SURGE VOLTAGE

(> V

B

+2V) DETECTED?

NO

NO

YES

YES

AK204017

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-628

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. Check harness connector B-105 at EGR valve for 
damage.

Q: Is the harness connector in good condition?

YES : Go to Step 2.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 12.

1

2 3

4

5 6

AK303137AB

B-105(GR)

CONNECTOR: B-105

EGR 
VALVE

BRAKE FLUID
RESERVOIR

HARNESS 
CONNECTOR: 
COMPONENT SIDE