Mitsubishi Outlander (2003+). Manual — part 54

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MFI)

13A-79

TROUBLE JUDGMENT

Judgment Criteria

œ

The engine coolant temperature is approximately.
20

•

C or higher.

œ

The oxygen sensor heater (rear) is in "ON" posi-
tion.

œ

The engine speed is 50 r/min or more.

œ

The battery voltage is 11

-

16 V.

Judgment Criteria

œ

The heater current of front oxygen sensor heater
(rear) is below 0.2 A or above 3.5 A for 1 second.

PROBABLE CAUSE

œ

Failed oxygen sensor heater (rear)

œ

Open/short circuit in oxygen sensor (rear) circuit
or loose connector contact

œ

Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Connector check: C-18 oxygen sensor
(rear) connector

Q: Is the check result normal?

YES :

Go to Step 2 .

NO :

Repair.

STEP 2. Measure resistance at C-18 oxygen
sensor (rear) connector.

œ

Disconnect connector, and measure at sensor
side.

œ

Resistance between terminal No. 1 and No. 2.

OK: 11

-

18

W

Q: Is the check result normal?

YES :

Go to Step 3 .

NO :

Replace oxygen (rear) sensor.

STEP 3. Measure voltage at C-18 oxygen sensor
(rear) connector.

œ

Disconnect connector, and measure at harness
side.

œ

Ignition switch: ON

œ

Voltage between terminal No. 2 and earth.

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 5 .

NO :

Go to Step 4 .

AK300270

1 2

3 4

AB

Connector: C-18

Oxygen sensor (rear)

C-18

Harness side
connector

AK300270

1 2

3 4

AB

Connector: C-18

Oxygen sensor (rear)

C-18

Harness side
connector

AK300270

1 2

3 4

AB

Connector: C-18

Oxygen sensor (rear)

C-18

Harness side
connector

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MFI)

13A-80

STEP 4. Connector check: B-17X engine control
relay connector

Q: Is the check result normal?

YES :

Check intermediate connector C-17, and

repair if necessary. If intermediate
connector is normal, check and repair
harness between C-18 (terminal No. 2)
oxygen sensor (rear) connector and B-17X
(terminal No. 1) engine control relay
connector.

œ

Check power supply line for
open/short circuit.

NO :

Repair.

STEP 5. Measure voltage at C-136 engine-ECU
connector.

œ

Measure engine-ECU terminal voltage.

œ

Ignition switch: ON

œ

Voltage between terminal No. 54 and earth.

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 8 .

NO :

Go to Step 6 .

STEP 6. Connector check: C-136 engine-ECU
connector

Q: Is the check result normal?

YES :

Go to Step 7 .

NO :

Repair.

AK300254

82

78

8180

89

90

91

92

79

87

71

74 73 72

76 75

77

85

88

83

84

86

AB

CONNECTOR: C-137

C-137

Harness side connector

AK300270

1 2

3 4

AB

Connector: C-18

Oxygen sensor (rear)

C-18

Harness side
connector

AK300268

58

60

61

53 52 51

55 54

56

59

62

57

AB

CONNECTOR: C-136

C-136

Harness side connector

AK300268

58

60

61

53 52 51

55 54

56

59

62

57

AB

CONNECTOR: C-136

C-136

Harness side connector

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MFI)

13A-81

STEP 7. Check harness between C-18 (terminal
No. 1) oxygen sensor connector and C-136
(terminal No. 54) engine-ECU connector.

œ

Check earthing line for open/short circuit.

Q: Is the check result normal?

YES :

Replace engine-ECU.

NO :

Repair.

STEP 8. Connector check: C-136 engine-ECU
connector

Q: Is the check result normal?

YES :

Go to Step 9 .

NO :

Repair.

AK300270

1 2

3 4

AB

Connector: C-18

Oxygen sensor (rear)

C-18

Harness side
connector

AK300268

58

60

61

53 52 51

55 54

56

59

62

57

AB

CONNECTOR: C-136

C-136

Harness side connector

AK300268

58

60

61

53 52 51

55 54

56

59

62

57

AB

CONNECTOR: C-136

C-136

Harness side connector

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MFI)

13A-82

STEP 9. Check harness between C-18 (terminal
No. 2) oxygen sensor connector and B-17X
(terminal No. 1) engine control relay connector.

NOTE: Before checking harness, check intermediate
connector C-17, and repair if necessary.

œ

Check power supply line for damage.

Q: Is the check result normal?

YES :

Go to Step 10 .

NO :

Repair.

STEP 10. Check harness between C-18 (terminal
No. 1) oxygen sensor connector and C-136
(terminal No. 54) engine-ECU connector.

œ

Check earthing line for damage.

Q: Is the check result normal?

YES :

Go to Step 11 .

NO :

Repair.

STEP 11. Check the trouble symptoms.

Q: Does trouble symptom persist?

YES :

Replace engine-ECU.

NO :

Intermittent malfunction (Refer to GROUP
00

-

How to Use

Troubleshooting/Inspection Service Points

3

00

).

AK300270

1 2

3 4

AB

Connector: C-18

Oxygen sensor (rear)

C-18

Harness side
connector

AK300255

2

1

3

4

Relay box’s
triangle marks

AB

CONNECTOR: B-17X

B-17X

Harness side
connector

AK300270

1 2

3 4

AB

Connector: C-18

Oxygen sensor (rear)

C-18

Harness side
connector

AK300268

58

60

61

53 52 51

55 54

56

59

62

57

AB

CONNECTOR: C-136

C-136

Harness side connector