Mitsubishi Eclipse. Manual - part 427

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-251

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

• Right bank heated oxygen sensor (front) deterio-

rated.

• ECM failed. <M/T>

• PCM failed. <A/T>

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

• MB998464:Test Harness

STEP 1. Using scan tool MB991958, check data list item 39: 
Heated Oxygen Sensor Bank 1, Sensor 1 (right front).

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Start the engine and run at idle.
(3) Set scan tool MB991958 to the data reading mode for item 

39, Heated Oxygen Sensor Bank 1, Sensor 1 (right front).

(4) Warm up the engine, 2,500 r/min.

• Output voltage repeats 0.4 volt or less and 0.6 − 1.0 volt 

10 times or more within 10 seconds.

(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use Troubleshooting/ 
Inspection Service Points 

P.00-6

.

NO :  Replace the right bank heated oxygen sensor (front). 

Then go to Step 2.

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-252

STEP 2. Check the right bank heated oxygen sensor 
(front).
(1) Disconnect the right bank heated oxygen sensor (front) 

connector B-27 and connect test harness special tool, 
MD998464, to the connector on the right bank heated 
oxygen sensor (front) side.

(2) Warm up the engine until engine coolant temperature 

reaches 80

°C (176°F) or higher.

CAUTION

Be very careful when connecting the jumper wires; incor-
rect connection can damage the right bank heated oxygen 
sensor (front).

(3) Use the jumper wires to connect terminal No. 1 (red clip) to 

the positive battery terminal and terminal No. 3 (blue clip) to 
the negative battery terminal.

(4) Connect a digital volt meter between terminal No. 2 (black 

clip) and terminal No. 4 (white clip).

(5) While repeatedly revving the engine, measure the right 

bank heated oxygen sensor (front) output voltage.

Standard value: 0.6 

− 1.0 volt

Q: Is the voltage between 0.6 and 1.0 volt?

YES : Go to Step 3.
NO :  Replace the right bank heated oxygen sensor (front). 

Then go to Step 4.

AK300409

1

2

3

4

RIGHT BANK 
HEATED OXYGEN
SENSOR (FRONT)

AB

B-27 (B)

CONNECTOR: B-27

HARNESS CONNECTOR:
COMPONENT SIDE

AKX01625AC

BLUE

RED

BLACK

JUMPER
WIRES

WHITE

MD998464

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-253

STEP 3. Check harness connector B-27 at right bank 
heated oxygen sensor (front) and harness connector C-58, 
C-62 at ECM or C-55, C-59 at PCM for damage.
Q: Is the harness connector in good condition?

YES : Replace the PCM. Then go to Step 4.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 4.

AK300409

1

2

3

4

RIGHT BANK 
HEATED OXYGEN
SENSOR (FRONT)

AB

B-27 (B)

CONNECTOR: B-27

HARNESS CONNECTOR:
COMPONENT SIDE

AK300441

65

43
50

42
49

41
48
60

61

64

46

47

58

59

67

68

45

56
66

52 51

44

53

62

54

63

57

55

80

87

81

94

85

82

84

93

86

98

99

74

92

73

83

88

91

95

97 96

100

89

78

71

90

76

77

75

72
79

CONNECTORS: C-58, C-62 <M/T>

C-58 (GR)

C-62 (GR)

AB

C-62 HARNESS CONNECTOR:
COMPONENT SIDE

C-58 HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-254

STEP 4. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to 

Diagnostic Function 

− OBD-II Drive Cycle − Procedure 4 − 

Heated Oxygen Sensor Monitor 

P.13B-7

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0133 set?

YES : Retry the troubleshooting.
NO :  The inspection is complete.

DTC P0134: Heated Oxygen Sensor Circuit No Activity Detected (bank 1, sensor 1)

.

HEATED OXYGEN SENSOR CIRCUIT NO 
ACTIVITY DETECTED (BANK 1, SENSOR 1) 
CIRCUIT

• Refer to DTC P0132 − Heated Oxygen Sensor 

Circuit High Voltage (bank 1, sensor 1) 

P.13B-242

.

• Refer to DTC P0201, P0203, P0205 − Injector 

Circuit 

P.13B-510

.

.

CIRCUIT OPERATION

• Refer to DTC P0132 − Heated Oxygen Sensor  

Circuit High Voltage (bank 1, sensor 1) 

P.13B-242

.

• Refer to DTC P0201, P0203, P0205 − Injector 

Circuit 

P.13B-510

.

.

TECHNICAL DESCRIPTION

• The ECM <M/T> or PCM <A/T> effects air/fuel 

ratio feedback control in accordance with the sig-
nals from the right bank heated oxygen sensor 
(front).

• If the right bank heated oxygen sensor (front) has 

deteriorated, corrections will be made by the right 
bank heated oxygen sensor (rear).

• DTC P0134 is stored when abnormality of the 

air/fuel ratio feedback control system is detected.

.

DESCRIPTIONS OF MONITOR METHODS
Right bank heated oxygen sensor (front) output volt-

age does not cross 0.5 volt within specified 
period.

.

AK300459

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

98

78

71

88

89

76

77

72
79
91

73
80

74

75

81
92

82

83

93

84

85

94

86

87

95

96

90

97

CONNECTORS: C-55, C-59 <A/T>

C-55 (GR)

C-59 (GR)

AB

C-59 HARNESS CONNECTOR:
COMPONENT SIDE

C-55 HARNESS CONNECTOR:
COMPONENT SIDE