Mitsubishi Eclipse / Eclipse Spyder (2000-2002). Service and repair manual — part 105

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-119

TECHNICAL DESCRIPTION

•

The heated oxygen sensor (front) detects the
concentration of oxygen in the exhaust gas; it
converts those data to voltage, and inputs the
resulting signals to the ECM <M/T> or PCM <A/
T>.

•

When the heated oxygen sensor (front) begins to
deteriorate, the heated oxygen sensor signal
response becomes poor.

•

The ECM <M/T> or PCM <A/T> forcibly varies
the air/fuel mixture to make it leaner and richer,
and checks the response speed of the heated
oxygen sensor (front). In addition, the ECM <M/
T> or PCM <A/T> also checks for an open circuit
in the heated oxygen sensor (front) output line.

DTC SET CONDITIONS

Check Conditions

•

Engine coolant temperature is higher than 50

°

C

(176

°

F).

•

Engine speed is at between 1,200 and 3,000 r/
min.

•

Volumetric efficiency is at between 25 and 60
percent.

•

Intake air temperature is higher than -10

°

C (14

°

F).

•

Barometric pressure is higher than 76 kPa (11
psi).

•

Under the closed loop air/fuel control.

•

ECM <M/T> or PCM <A/T> dose not judge to be
idling state.

Judgment Criteria

•

The heated oxygen sensor (front) sends "lean"
and "rich" signals alternately eight times
(Response time 1.1 or equivalent) or less for 10
seconds.

•

Only one monitor during one drive cycle

NOTE: If the sensor switch time is longer than the
Judgment Criteria due to the MUT-II OBD-II test
Mode

−

H02S Test Results, it is assumed that the

heated oxygen sensor has deteriorated. If it is
short, it is assumed that the harness is damaged
or has a short circuit.
If the heated oxygen sensor signal voltage has
not changed even once (lean/rich) after the DTC
was erased, the sensor switch time will display as
0 seconds.

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

•

Heated oxygen sensor (front) deteriorated.

•

Open circuit in heated oxygen sensor (front)
output line.

•

Open circuit in heated oxygen sensor (front)
ground line.

•

ECM failed. <M/T>

•

PCM failed. <A/T>

DIAGNOSIS

Required Special Tools
MB991502: Scan Tool (MUT-II)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-120

STEP 1. Using scan tool MB991502, check data list item 11:
Heated Oxygen Sensor (front).

CAUTION

To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK" (OFF) position before
connecting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Start the engine and run at idle.
(3) Set scan tool MB991502 to the data reading mode for item

11, Heated Oxygen Sensor (front).

(4) Warm up the engine, 2500r/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 heated oxygen sensor (front). Then go to

Step 2.

STEP 2. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to,

Procedure 6

−

Other Monitor (

P.13A-5

).

(2) Check the diagnostic trouble code (DTC).

Q: Is the DTC P0133 is output?

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

DTC P0134: O

2

Sensor Circuit No Activity Detected (sensor 1)

O

2

Sensor Circuit No Activity Detected (sensor 1)

•

Refer to, DTC P0130 Heated Oxygen Sensor
(front) Circuit (

P.13A-109

).

•

Refer to, DTC P0201, P0202, P0203, P0204

−

Injector Circuit (

P.13A-161

).

CIRCUIT OPERATION

•

Refer to, DTC P0130 Heated Oxygen Sensor
(front) Circuit (

P.13A-109

).

•

Refer to, DTC P0201, P0202, P0203, P0204

−

Injector Circuit (

P.13A-161

).

TECHNICAL DESCRIPTION

•

The heated oxygen sensor (front) detects the
concentration of oxygen in the exhaust gas; it
converts those data to voltage, and inputs the
resulting signals to the ECM <M/T> or PCM <A/
T>.

•

When the heated oxygen sensor (front) begins to
deteriorate, the heated oxygen sensor signal
response becomes poor.

•

The ECM <M/T> or PCM <A/T> forcibly varies
the air/fuel mixture to make it leaner and richer,
and checks the response speed of the heated
oxygen sensor (front). In addition, the ECM <M/
T> or PCM <A/T> also checks for an open circuit
in the heated oxygen sensor (front) output line.

DTC SET CONDITIONS

Check Conditions

•

Thirty seconds or more have passed since the
starting sequence was completed.

•

Engine coolant temperature is higher than 81

°

C

(178

°

F).

•

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

•

Volumetric efficiency is higher than 30 percent.

•

Under the closed loop air/fuel control.

AKX01177

16 PIN

MB991502

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-121

•

Monitoring time: 30seconds.

Judgment Criteria

•

Multiport fuel injection system does not enter the
closed loop control within about 30 seconds of
meeting all criteria above.

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

•

Heated oxygen sensor (front) deteriorated.

•

Open circuit in heated oxygen sensor (front)
output line.

•

Open circuit in heated oxygen sensor (front)
ground line.

•

ECM failed. <M/T>

•

PCM failed. <M/T>

DIAGNOSIS

Required Special Tools
MD998464: Test Harness

STEP 1. Check the exhaust leaks.

Q: Are there any abnormalities?

YES : Go to Step 2.
NO : Repair it. Then go to Step 11.

STEP 2. Check the intake system vacuum leak.

Q: Are there any abnormalities?

YES : Go to Step 3.
NO : Repair it. Then go to Step 11.

STEP 3. Check connector B-17 at the heated oxygen
sensor (front) 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 11.

AK000272AB

AK000272

CONNECTOR : B-17

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

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STEP 4. Check the heated oxygen sensor (front).
(1) Disconnect the heated oxygen sensor (front) connector B-

17 and connect test harness special tool, MD998464 to the
connector on the 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;
incorrect connection can damage the heated oxygen
sensor (front).
(3) Use the jumper wires to connect terminal 1 (red clip) to the

positive battery terminal and terminal 3 (blue clip) to the
negative battery terminal.

(4) Connect a digital volt meter between terminal 2 (black clip)

and terminal 4 (white clip).

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

oxygen sensor (front) output voltage.

Standard value: 0.6

−

1.0 V

Q: Is the voltage at the standard value?

YES : Go to Step 5.
NO : Replace the heated oxygen sensor (front). Then go to

Step 11.

STEP 5. Check connector B-01, B-02, B-05, B-06 at injector
for damage.
Q: Is the connector in good condition?

YES : Go to Step 6.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection (

P.00E-2

). Then go to Step 11.

ACX02476

CONNECTOR : B-17

HEATED OXYGEN
SENSOR (FRONT)

AD

AKX01624

HEATED
OXYGEN
SENSOR
EQUIPMENT
SIDE
CONNECTOR

MD998464

BLUE

RED

AC

AKX01625AC

BLUE

RED

BLACK

JUMPER
WIRES

WHITE

MD998464

AK000273AB

AK000273

CONNECTOR : B-01, B-02, B-05, B-06

B-01 B-02 B-05 B-06