Mitsubishi Galant. Manual — part 174

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-377

CIRCUIT OPERATION

•

The PCM sends a duty signal to the fan controller
according to engine coolant temperature, vehicle
speed, and the condition of the A/C switch. (The
closer the average voltage at the terminal comes
to five volts, the higher the fan speed becomes).

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

））

）

•

Malfunction of the fan motor relay.

•

Malfunction of the fan motor.

•

Malfunction of the fan controller.

•

Improper connector contact, open or short-
circuited harness wire.

•

PCM failed.

DIAGNOSIS

STEP 1. Check connector C-39 at PCM for damage.
Q: Is the 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 confirm that the

malfunction symptom is eliminated.

STEP 2. Check the output voltage at PCM harness side
connector C-39.
(1) Disconnect the C-39 and measure at the harness side.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 18 and ground.

•

Voltage should be between 4.8 and 5.2 volts. (Fan
rotates at high speed.)

(4) Connect a jumper cable between terminal 18 and ground.

•

The fan should stop.

(5) Turn the ignition switch to the "LOCK"(OFF) position.

Q: Is the voltage and fan condition normal?

YES : Replace the PCM. Then confirm that the malfunction

symptom is eliminated.

NO : Go to Step 3.

ACX02501 AE

CONNECTOR : A-30

FAN
CONTROLLER

AK000280

CONNECTOR : C-39

PCM

AW

AK000401

8 7

6 5

4 3

2

1
9

10

11

12

13

14

15

16

17

18

19

20

21

22

23
3534

33 32

30

29 28 27 26

25 24

C-39 HARNESS
SIDE CONNECTOR

AC

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-378

STEP 3. Check for open circuit and short circuit to ground
and harness damage between fan controller A-30 terminal
2 and PCM connector C-39 terminal 18.
NOTE: Check harness after checking intermediate connector
C-04. If intermediate connector is damaged, repair or replace
them. Refer to GROUP 00E, Harness Connector
Inspection(

P.00E-2

). Then confirm that the malfunction

symptom is eliminated.

Q: Is the harness wire in good condition?

YES : Refer to GROUP 14-Engine Cooling Diagnosis-

Symptom Chart(

P.14-3

).

NO : Repair it. Then confirm that the malfunction symptom

is eliminated.

ACX02501 AE

CONNECTOR : A-30

FAN
CONTROLLER

AK000280

CONNECTOR : C-39

PCM

AW

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-379

INSPECTION PROCEDURE 29: Power supply system and ignition switch-IG system.

AK000482

4

1 2
3

6

2 3

4 5 6

BL

ACK

-

WHITE

1

1

3

2

4

1

4

8

7

2

6

3

5

5

BL

ACK

-

WHITE

BL

ACK

-

WHITE

BL

ACK

-

WHITE

RED

-BL

ACK

RED

-BL

ACK

RED

-BL

ACK

RED

RED

RED

SK

Y BL

UE

RED

-

WHITE

RED

-

WHITE

RED

-

WHITE

RED

-

WHITE

WHITE

WHITE

BL

ACK

BL

ACK

BL

ACK

BATTERY

R

IG2

ST

LOCK

ACC

IG1

C-58

C-73
MU801331

IGNITION
SWITCH

2

6

5

JUNCTION
BLOCK

98

C-04
MU801333

66

MFI
RELAY

A-21X

3

4

1

2

49

BATTERY
BACK UP

47

41

POWER
SOURCE

48

42

POWERTRAIN CONTROL
MODULE(PCM)

C-40
(MU803781)

C-41
(MU803782)

3

8

13

29

98

78

71

88 89

76 77

72
79
91

73
80

74

75

81
92

8283
93

8485

94

8687

9596

90

97

42 43
48 49 50 51 52 53 54 55 56 57

46

45

44

58 59

60 61 62 63

64 65 66

47

41

15 16

26 27 28 29

32 33 34

17 18 19 20 21 22 23 24 25

30 31

36 37

35

38

10

11 12 13

1 2 3

4 5 6 7 8 9

14

C-66

C-04

25

C-66

27

C-17

C-17

7 8

5

3 4

35

34

10 11 12

2122 23 24

13 14 15

25 26 27

16

28

17

18 19 20

29

30 31

32 33

36 37

38

9

1 2

6

4

DEDICATED
FUSE

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-380

CIRCUIT OPERATION

•

Battery positive voltage is applied to the MFI
relay (terminals 3, 4).

•

When the ignition switch is turned to the "ON"
position, The battery positive voltage is applied to
the PCM (terminal 98). When the battery positive
voltage is applied, the PCM turns the power
transistor in the PCM "ON" and grounds the MFI
relay coil. With this, the MFI relay turns "ON" and
the battery positive voltage is supplied to the
PCM (terminal 41, 47) from the MFI relay
(terminal 1).

AK000280

CONNECTORS : C-40, C-41

C-41

C-40

PCM

AX

AK000632 AB

CONNECTOR:C-66

AK000634 AB

CONNECTOR:C-58

AK000633 AE

CONNECTOR:C-04

AK000555AB

CONNECTOR : A-21X

MFI RELAY

AK000631AC

CONNECTOR:C-73

AK000566AB

CONNECTOR:C-17