Mitsubishi Colt Ralliart. Manual - part 711

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-169

STEP 4. After replacing the immobilizer-ECU, 
re-check the trouble symptoms.

Q: Is the check result normal? 

YES : 

Replace engine-ECU.

NO : 

Check end.

Code No. P0603: EEPROM Malfunction

FUNCTION

• The engine-ECU checks whether idling compen-

sation value and other relevant data are stored in 
memory.

TROUBLE JUDGEMENT

Check Condition

• Ignition switch: ON

Judgement Criterion

• Last learning-date switch were written when igni-

tion switch was in OFF is not stored correctly.

PROBABLE CAUSE

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

• Reconfirmation of diagnosis code.

Q: Is the diagnosis code output?

YES : 

Replace the engine-ECU.

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use 

Troubleshooting/Inspection Service Points 

− 

How to Cope with Intermittent Malfunctions 

P.00-13

).

Code No. P0606: Microcomputer Malfunction System

FUNCTION

• The engine-ECU checks whether there is any 

abnormality in the microcomputer that controls 
the throttle valve operation.

TROUBLE JUDGEMENT

Check Condition

• Ignition switch is in "ON" position.

• Battery voltage is more than 6.3 V.

Judgement Criterion

• Main microcomputer reference voltage is 

abnomal.

PROBABLE CAUSE

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

• Reconfirmation of diagnosis code.

Q: Is the diagnosis code output?

YES : 

Replace engine-ECU.

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use 

Troubleshooting/Inspection Service Points 

− 

How to Cope with Intermittent Malfunctions 

P.00-13

).

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-170

Code No. P0622: Alternator FR Terminal System

OPERATION

• This system provides data on energized state of 

the field coil from the alternator (terminal No. 4) to 
the engine-ECU (terminal No. 65).

FUNCTION

• The system provides the engine-ECU with a sig-

nal that shows the energizing duty ratio of the 
alternator field coil.

• Using this signal, the engine-ECU determines the 

alternator output current (electric load), based on 
which the ECU controls the engine idling speed 
accordingly.

TROUBLE JUDGEMENT

Check Condition

• After engine starts.

Judgement Criterion

• Input voltage from the alternator FR terminal is 

battery voltage for 20 seconds.

PROBABLE CAUSES

• Failed alternator

• Short circuit in or damage to alternator circuit, or 

loose connector contact

• Failed engine-ECU

AK402692

1

2

3 4

19

21

20

18

17

16

15

14

1213

11

8 9

L

10

37
52 53 54 555657585960616263646566

38 39 404142434445464748495051

22 23 24 252627282930313233343536

7

5

3

1

6

4

2

Engine-ECU

Alternator

Y-B

IC voltage
regulator

65

4 

Alternator Circuit

      A-131
(MU802046)

A-114

Wire colour code
B: Black  LG: Light green  G: Green  L: Blue  W: White  Y: Yellow  SB: Sky blue  BR: Brown  O: Orange  GR: Gray
R: Red  P: Pink  V:Violet

  P: Purple

AE

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-171

DIAGNOSIS PROCEDURE

STEP 1. Connector check: A-131 alternator 
connector

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair or replace.

STEP 2. Perform voltage measurement at A-131 
alternator connector.

•

Disconnect connector, and measure at harness side.

• Ignition switch: ON

• Voltage between terminal No. 4 and earth.

OK: System Voltage

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Go to Step 3.

STEP 3. Connector check: A-114 engine-ECU 
Connector

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Repair or replace.

2

1

3

4

AK402098

A-131(G)

Connector: A-131

Harness side 
connector

AC

2

1

3

4

AK402098

A-131(G)

Connector: A-131

Harness side 
connector

AC

AK402745

6

4

2

5

3

1

9

7

8

10

11

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52

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61

62

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64

65

66

L

AF

A-114

Connector: 

A-114

Harness side connector

Engine-ECU

Battery

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-172

STEP 4. Check harness between A-131 (terminal 
No. 4) alternator connector and A-114 (terminal 
No. 65) engine-ECU connector.

•

Check the output line for open circuit.

Q: Is the check result normal?

YES : 

Go to Step 5.

NO : 

Repair.

STEP 5. M.U.T.-III diagnosis code

• Reconfirmation of diagnosis code.

Q: Is the diagnosis code output?

YES : 

Replace the engine-ECU.

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use 

Troubleshooting/Inspection Service Points 

− 

How to Cope with Intermittent Malfunctions 

P.00-13

).

STEP 6. Perform voltage measurement at A-114 
engine-ECU connector.

•

Disconnect engine-ECU connector, and connect 

special tool power plant ECU check harness 
(MB991987), and measure the voltage on the 
check connector.

• Engine: Idling after warm-up

• Transmission: Neutral

• Radiator fan: Inactive

• Voltage between terminal No. 65 and earth.

OK: Switching the headlamps from OFF to 
ON causes the voltage to drop.

Q: Is the check result normal?

YES : 

Go to Step 7.

NO : 

Go to Step 9.

2

1

3

4

AK402098

A-131(G)

Connector: A-131

Harness side 
connector

AC

AK402745

6

4

2

5

3

1

9

7

8

10

11

12

13

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46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

L

AF

A-114

Connector: 

A-114

Harness side connector

Engine-ECU

Battery

AK402745

6

4

2

5

3

1

9

7

8

10

11

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47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

L

AF

A-114

Connector: 

A-114

Harness side connector

Engine-ECU

Battery

Main

Index

Group

TOC