Mitsubishi Eclipse. Manual — part 280

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-613

.

CIRCUIT OPERATION

• A 5-volt voltage is applied to the vehicle speed

sensor output terminal (terminal No. 3) from the
ECM (terminal No. 86). The vehicle speed sensor
generates a pulse signal when the output termi-
nal is opened and grounded.

.

TECHNICAL DESCRIPTION

• The vehicle speed sensor converts the vehicle

speed into pulse signals and inputs them to the
ECM.

• The vehicle speed sensor outputs a pulse signal

while the vehicle is driven.

• The ECM checks whether the pulse signal is out-

put.

.

AK300102

VEHICLE
SPEED
SENSOR

B-39 (B)

AB

CONNECTOR: B-39

AK300117

CONNECTOR: C-78

AB

C-78

AK300116

CONNECTOR: C-87

AB

C-87

AK300119

CONNECTOR: C-28

AB

C-28

AK300125

CONNECTOR: C-112

AB

C-112

AK300124

CONNECTOR: C-111

AB

C-111

AK300065

CONNECTOR: B-36

AB

B-36 (B)

AK300060

ECM

CONNECTOR: C-60 <M/T>

AE

C-60 (G)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L>

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DESCRIPTIONS OF MONITOR METHODS

• If the vehicle speed sensor output does not

change while the vehicle is being driven in the
medium- to high-speed range, a malfunction is
determined to have occurred.

.

MONITOR EXECUTION

• Continuous

.

MONITOR EXECUTION CONDITIONS (Other
monitor and Sensor)

Other Monitor (There is no temporary DTC stored

in memory for the item monitored below)

• Not applicable

Sensor (The sensor below is determined to be

normal)

• Volume Airflow Sensor

.

DTC SET CONDITIONS (

LOGIC FLOW CHARTS

.

Check Conditions

• 2 seconds or more have passed the starting

sequence was completed.

• Engine speed is at between 2,000 and 4,000

r/min.

• Volumetric efficiency is at between 48 and 65

percent.

Judgement Criteria

• Vehicle speed sensor output voltage has not

changed (no pulse signal is input) for 2 seconds.

.

OBD-II DRIVE CYCLE PATTERN
None

.

START

MONITORING

CONDITIONS

END

NO

NO

NO

YES

YES

YES

MALFUNCTION

GOOD

OUTPUT FREQUENCY

=/ 0Hz

CONTINUOUS

FAILURE FOR 2 secs

AK200919

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-615

DTC SET CONDITIONS

Check Conditions

• 2 seconds or more have passed the starting

sequence was completed.

• Engine speed is at between 2,000 and 4,000

r/min.

• Volumetric efficiency is at between 48 and 65

percent.

Judgement Criteria

• Vehicle speed sensor output voltage has not

changed (no pulse signal is input) for 2 seconds.

.

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

• Vehicle speed sensor failed.

• Open or shorted vehicle speed sensor circuit, or

harness damage, or connector damage.

• ECM failed.

DIAGNOSIS

Required Special Tools:

• MB991958 (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

STEP 1. Using scan tool MB991958, check data list item 24:
Vehicle Speed Sensor.

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.
(3) Set scan tool MB991958 to the data reading mode for item

24, Vehicle Speed Sensor.

• Check that the speedometer and MB991958 display

speed match when traveling at a vehicle speed of 40
km/h (25 mph).

(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.

STEP 2. Check speed meter.
Q: Is the speed meter functioning?

YES : Go to Step 3.
NO : Go to Step 8.

AK300810

AB

MB991911

16-PIN

MB991827

MB991824

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-616

STEP 3. Using the oscilloscope, check the sensor output
voltage at ECM connector C-60.
(1) Do not disconnect the ECM connector C-60.
(2) Disconnect the combination meter connector and

auto-cruise control-ECU connector.

(3) Connect the oscilloscope probe to ECM terminal No. 86 by

backprobing.

(4) Start the engine.

(5) Check the waveform.

• The waveform should show a pattern similar to the illus-

tration while the vehicle is being moved.

(6) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the waveform normal?

YES : Go to Step 4.
NO : Go to Step 6.

STEP 4. Check connector C-60 at ECM for damage.
Q: Is the connector in good condition?

YES : Go to Step 5.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 17.

AK000324

ECM CONNECTOR

OSCILLOSCOPE

OSCILLOSCOPE
PLOBE

7172 73 74 75 76 77 78 79 80 81

82 83 84 85 86 87 88 89 90 9192

AB

AKX01562

AKX01562

(ms)

0

(V)

NORMAL WAVEFORM

AB

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