Mitsubishi 380. Manual - part 518

MULTIPORT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MPI)

13A-164

STEP 4. Check for short to heater circuit ground harness
wire between right bank heated oxygen sensor (front)
connector B-09 (terminal No. 1) and ENGINE-ECU
connector B-20 (terminal No. 45).
Q: Is the harness wire in good condition?

YES : Go to Step 5.
NO : Repair or replace it. Then go to Step 6.

AK303048

B-09 (B)

CONNECTOR: B-09

THROTTLE BODY

RIGHT BANK

HEATED OXYGEN

SENSOR (FRONT)

HARNESS

CONNECTOR:

COMPONENT SIDE

16DB400A

COVER

ENGINE

CONTROL

UNIT

AIR

CLEANER

MULTIPORT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MPI)

13A-165

STEP 5. Using diagnostic tool, check data list item AC:
Heated Oxygen Sensor Bank 1, Sensor 1 (right front).

CAUTION

To prevent damage to diagnostic tool, always turn the igni-
tion switch to the "LOCK" (OFF) position before connect-
ing or disconnecting diagnostic tool .
(1) Connect diagnostic tool to the data link connector.
(2) Start the engine and run at idle.
(3) Ensure engine is at running temperature (80

° C or higher).

(4) Set diagnostic tool to the data reading mode for item AC,

Heated Oxygen Sensor Bank 1, Sensor 1 (right front).

• Warm engine. When the engine is revved up and down,

the output voltage should cycle between 0.1 to 0.8 volt.

• Warm engine. When the engine is idling, the output volt-

age should alternate between 0.1 to 0.6 - 1.0 volt.

(5) Turn the ignition switch to the "LOCK" (OFF) position.

NOTE: If data list readings are low or appear slow to cycle
during check the sensor is likely to be malfuctioning. Ensure
wiring and connector checks are performed prior to replac-
ing sensor.

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

− How to

Cope with Intermittent Malfunctions

P.00-14

NO : Replace the faulty oxygen sensor. Then go to Step 6.

STEP 6. Test the EOBD drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to

Diagnostic Function

− EOBD Drive Cycle −

P.13A-11

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

Q: Is DTC P0130 set?

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

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MPI)

13A-166

DTC P0131: Heated Oxygen Sensor Circuit Low Voltage (bank 1, sensor 1).

CIRCUIT OPERATION

• A voltage corresponding to the oxygen concen-

tration in the exhaust gas is sent to the
ENGINE-ECU (terminal No. 45) from the output
terminal (terminal No. 1) of the right bank heated
oxygen sensor (front).

• Terminal No. 2 of the right bank heated oxygen

sensor (front) is grounded with ENGINE-ECU
(terminal No. 44).

TECHNICAL DESCRIPTION

• The right bank 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
ENGINE-ECU.

• When the right bank heated oxygen sensor

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

• The ENGINE-ECU forcibly varies the air/fuel mix-

ture to make it leaner and richer, and checks the
response speed of the right bank heated oxygen
sensor (front). In addition, the ENGINE-ECU also
checks for an open circuit in the right bank
heated oxygen sensor (front) output line.

DTC SET CONDITIONS

Check Conditions

• Battery voltage < 11.02 volts

• Engine coolant temperature is higher than 80°C.

Judgement Criteria

• Internal Resistance of the Nernst - cell is equal or

greater than a modelled resistance based on the
heating output of the O2-sensor and the mod-
elled exhasused gas temperature

• Idling.

• MIL is activated after 2 Drive cycles.

• No limp home.

EOBD DRIVE CYCLE PATTERN

Refer to Diagnostic Function

− EOBD Drive Cycle −

P.13A-11

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

• Right bank heated oxygen sensor (front) failed.

• Short circuit to ground in right bank heated oxy-

gen sensor (front) output line.

• Wiring harness or connector damage.

• Refer to component locations GROUP-

• Refer to configuration diagrams GROUP-

• Refer to circuit diagrams GROUP-

AK303047

B-09 (B)

CONNECTOR: B-09

THROTTLE BODY

RIGHT BANK

HEATED OXYGEN

SENSOR (FRONT)

16DB400A

COVER

ENGINE

CONTROL

UNIT

AIR

CLEANER

MULTIPORT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MPI)

13A-167

DIAGNOSIS

Required Special Tools:

• Diagnostic tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

• MB992044: ENGINE-ECU Check Harness

STEP 1. Using diagnostic tool, check data list item AC:
Heated Oxygen Sensor Bank 1, Sensor 1 (right front).

CAUTION

° C or higher).

(4) Set diagnostic tool to the data reading mode for item AC,

Heated Oxygen Sensor Bank 1, Sensor 1 (right front).

• Warm engine. When the engine is revved up and down,

the output voltage should cycle between 0.1 to 1.0 volt.

• Warm engine. When the engine is idling, the output volt-

age should alternate between 0.1 to 0.6 -1.0 volt.

(5) Turn the ignition switch to the "LOCK" (OFF) position.

NOTE: If data list readings are consistantly low or appear
slow to cycle( should cycle every 0.5-1.0 sec.) during check
the sensor is likely to be malfuctioning. Ensure wiring and
connector checks are performed prior to replacing sensor.

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

− How to

Cope with Intermittent Malfunctions

P.00-14

NO : Go to Step 2.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

Content .. 516 517 518 519 ..