Mitsubishi Eclipse. Manual — part 423

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-235

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• 3 minutes or more have passed since the starting

sequence was completed.

• Right bank heated oxygen sensor (front) signal

voltage has continued to be 0.2 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.

• Volume airflow sensor output frequency is 75 Hz

or more.

START

V

F

> =4.5V

2secs HAS PASSED

YES

YES

YES

NO

NO

NO

MALFUNCTION

MONITORING

CONDITIONS

YES

NO

MONITORING

CONDITIONS

+5V ON

AK301436

V

F

< 0.2V

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-236

• At least 20 seconds have passed since fuel shut

off control was canceled.

• Monitoring time: 10 seconds.

Judgement Criteria

• Making the air/fuel ratio 15 percent for 10 sec-

onds richer does not result in raising the heated
oxygen sensor (front) output voltage beyond 0.2
volt.

.

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: )

• Right bank heated oxygen sensor (front) failed.

• Short circuit in right bank heated oxygen sensor

(front) output line.

• ECM failed. <M/T>

• PCM failed. <A/T>

• Connector damage.

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

• MD998464: 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).

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

output voltage should be 0.6 to 1.0 volt.

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

output voltage should repeat 0.4 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-237

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 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 5.

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-238

STEP 3. Check connector B-27 at right bank heated
oxygen sensor (front) and connector C-62 at ECM <M/T> or
connector C-59 at PCM <A/T> for damage.
Q: Is the connector in good condition?

YES : Go to Step 4.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 5.

AK300409

1

2

3

4

RIGHT BANK
HEATED OXYGEN
SENSOR (FRONT)

AB

B-27 (B)

CONNECTOR: B-27

HARNESS CONNECTOR:
COMPONENT SIDE

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