Mitsubishi Colt Ralliart. Manual — part 703

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-137

STEP 6. Check harness between A-105 (terminal
No. 2) No. 4 injector connector and A-114
(terminal No. 24) engine-ECU connector.

• Check earthing line for damage.

Q: Is the check result normal?

YES :

Go to Step 7 .

NO :

Repair the damaged harness wire.

STEP 7. Fuel pressure measurement.

• Fuel pressure measurement (Refer to Fuel Pres-

sure Test

P.13B-358

).

Q: Is the check result normal?

YES :

Go to Step 8 .

NO :

Repair the fuel pressure.

STEP 8. M.U.T.-III diagnosis code.

• Reconfirmation of diagnosis code.

Q: Is the diagnosis code set?

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

).

AK402091

M

1

2

A-105(G)

AC

Connector: A-105

Harness side
connector

AK402745

6

4

2

5

3

1

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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-138

Code No. P0325: Detonation Sensor System

OPERATION

• The sensor signal is input to the engine-ECU (ter-

minal No. 20) from the detonation sensor (termi-
nal No. 2).

FUNCTION

• The detonation sensor detects vibration of the

cylinder block resulting from knocking and inputs
a signal to the engine-ECU.

• In response to the signal, the engine-ECU pro-

vides ignition-timing retarding control while
knocking condition persists.

TROUBLE JUDGEMENT

Check Conditions

• 2 seconds later from when engine starts

• Engine speed is more than 2,500 r/min.

• The volume efficiency is more than a prescribed

value.

Judgement Criterion

• When the amount of the change of continuous-

ness 200 times and the knock sensor output volt-
ages is minute.

PROBABLE CAUSES

• Failed detonation sensor

• Open/short circuit in or damage to detonation

sensor circuit, or loose connector contact

• Failed engine-ECU

AK402688

1 2

19

21

20

18

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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

20

21

Detonation sensor

B

R

2

1

A-128

A-114

Detonation Sensor Circuit

AD

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

Engine-ECU

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-139

DIAGNOSIS PROCEDURE

STEP 1. Connector check: A-128 detonation
sensor connector

Q: Is the check result normal?

YES :

Go to Step 2 .

NO :

Repair or replace.

STEP 2. Perform resistance measurement at
A-128 detonation sensor connector.

• Disconnect connector and measure at harness

side.

• Resistance between terminal No. 1 and earth.

OK: Continuity (2

Ω or less)

Q: Is the check result normal?

YES :

Go to Step 4 .

NO :

Go to Step 3 .

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

Q: Is the check result normal?

YES :

Check and repair if necessary the harness

between A-128 (terminal No. 1) detonation
sensor connector and A-114 (terminal No.
21) engine-ECU connector.

NO :

Repair or replace.

AK402094

2 1

AD

Connector: A-128

Harness side
connector

A-128

AK402094

2 1

AD

Connector: A-128

Harness side
connector

A-128

AK402745

6

4

2

5

3

1

9

7

8

10

11

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61

62

63

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-140

STEP 4. Connector check: A-114 engine-ECU
connector

Q: Is the check result normal?

YES :

Go to Step 5 .

NO :

Repair or replace.

STEP 5. Check harness between A-128 (terminal
No. 2) detonation sensor connector and A-114
(terminal No. 20) engine-ECU connector.

• Check output line for open/short circuit and dam-

age.

Q: Is the check result normal?

YES :

Go to Step 6 .

NO :

Repair.

AK402745

6

4

2

5

3

1

9

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54

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58

59

60

61

62

63

64

65

66

L

AF

A-114

Connector:

A-114

Harness side connector

Engine-ECU

Battery

AK402094

2 1

AD

Connector: A-128

Harness side
connector

A-128

AK402745

6

4

2

5

3

1

9

7

8

10

11

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63

64

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66

L

AF

A-114

Connector:

A-114

Harness side connector

Engine-ECU

Battery

Main

Index

Group

TOC