Mitsubishi Eclipse. Manual - part 463

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-395

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• 3 minutes or more have passed since the starting 

sequence was completed.

• Left bank heated oxygen sensor (rear) signal volt-

age has continued to be 0.15 volt or lower.

• Engine coolant temperature is higher than 76°C 

(169

°F).

• Engine speed is higher than 1,200 r/min.

• Volumetric efficiency is higher than 25 percent.

• Monitoring time: 7 seconds.

START

V

F

 > =4.5V

2secs HAS PASSED

YES

YES

YES

NO

NO

NO

MALFUNCTION

MONITORING

CONDITIONS

YES

NO

MONITORING

CONDITIONS

+5V ON

AK301440

V

F

 < 0.15V

10secs HAS PASSED

YES

YES

NO

NO

END

MALFUNCTION

GOOD

MODULATE A/F CONDITION TO RICH

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-396

Judgment Criteria

• Input voltage supplied to the ECM <M/T> or PCM 

<A/T> interface circuit is higher than 4.5 volts 
when 5 volts is applied to the left bank heated 
oxygen sensor (rear) output line via a resistor.

.

OBD-ll DRIVE CYCLE PATTERN
Refer to , Diagnostic Function 

− OBD-ll Drive Cycle − 

Procedure 6 

− Other Monitor 

P.13B-7

.

.

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

• Left bank heated oxygen sensor (rear) failed.

• Open or shorted circuit in left bank heated oxy-

gen sensor (rear) output line, or harness dam-
age.

• Open circuit in left bank heated oxygen sensor 

(rear) ground line, or harness damage.

• 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

• MB991316: Test Harness

STEP 1. Using scan tool MB991958, check data list item 59: 
Heated Oxygen Sensor Bank 2, Sensor 2 (left 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 Bank 2, Sensor 2 (let 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 :  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-397

STEP 2. Check the sensor output voltage at left bank 
heated oxygen sensor (rear) connector B-23 by 
backprobing.
(1) Do not disconnect the connector B-23.
(2) Start the engine and run at idle.
(3) Measure the voltage between terminal No. 4 and ground by 

backprobing.

• 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 measured voltage between 0.6 and 1.0 volt?

YES : Go to Step 3.
NO :  Go to Step 7.

AK300410

1

2

3

4

LEFT BANK 
HEATED OXYGEN
SENSOR (REAR)

CONNECTOR: B-23

AB

B-23 (GR)

HARNESS CONNECTOR:
COMPONENT SIDE

AKX01538AM

1 2

3 4

B-23 HARNESS 
CONNECTOR: 
HARNESS SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-398

STEP 3. Check the sensor output voltage at ECM 
connector C-62 <M/T> or PCM connector C-59 <A/T> by 
backprobing.
(1) Do not disconnect the connector C-62 <M/T> or C-59 

<A/T>.

(2) Start the engine and run at idle.

AK300460

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-59 <A/T>

C-59 (GR)

AB

HARNESS CONNECTOR:
COMPONENT SIDE

AK300445

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

CONNECTOR: C-62 <M/T>

C-62 (GR)

AB

HARNESS CONNECTOR:
COMPONENT SIDE