Mitsubishi Eclipse. Manual - part 198

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-285

STEP 5. Using scan tool MB991958, check data list item 59: 
Heated Oxygen Sensor (rear).

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 

59, Heated Oxygen Sensor (rear).

• Warming up the engine. When the engine is revved, the 

output voltage should repeat 0 volt and 0.6 to 1.0 volt 
alternately.

(4) 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 ECM or PCM. Then go to Step 14.

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-286

STEP 6. Check connector C-23 at heated oxygen sensor 
(rear) and connector C-60 at ECM <M/T> or connector C-57 
at PCM <A/T> for damage.
Q: Is the connector in good condition?

YES : Repair harness wire between heated oxygen sensor 

(rear) connector C-23 (terminal No. 1) and ECM 
connector C-60 (terminal No. 75) <M/T> or PCM 
connector C-57 (terminal No. 73) <A/T> because of 
open circuit or harness damage. Then go to Step 14.

NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 14.

AK300405

2

1

6 5 4 3

AB

C-23

HEATED OXYGEN
SENSOR (REAR)

CONNECTOR: C-23

HARNESS 
CONNECTOR:
HARNESS SIDE

AK300415

82

78

8180

89

90

91

92

79

87

71

74 73 72

76 75

77

85

88

83

84

86

CONNECTOR: C-60 <M/T>

AB

C-60 (G)

HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-287

STEP 7. Check connector C-23 at heated oxygen sensor 
(rear) for damage.
Q: Is the connector in good condition?

YES : Go to Step 8.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 14.

AK300735

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

CONNECTOR: C-57 <A/T>

C-57 (GR)

AB

HARNESS CONNECTOR:
COMPONENT SIDE

AK300405

2

1

6 5 4 3

AB

C-23

HEATED OXYGEN
SENSOR (REAR)

CONNECTOR: C-23

HARNESS 
CONNECTOR:
HARNESS SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-288

STEP 8. Check the continuity at heated oxygen sensor 
(rear) harness side connector C-23.
(1) Disconnect the connector C-23 and measure at the harness 

side.

(2) Check for the continuity between terminal No. 4 and 

ground.

• Should be less than 2 ohms.

Q: Is the continuity normal?

YES : Go to Step 11.
NO :  Go to Step 9.

AK300405

2

1

6 5 4 3

AB

C-23

HEATED OXYGEN
SENSOR (REAR)

CONNECTOR: C-23

HARNESS 
CONNECTOR:
HARNESS SIDE

AK000321AG

2

1

6 5 4 3

C-23 HERNESS 
CONNECTOR: C
OMPONENT SIDE