Mitsubishi Outlander (2013+). Manual — part 293

TROUBLESHOOTING

MULTIPOINT FUEL INJECTION (MPI)

13A-53

TROUBLE JUDGMENT

Check Conditions

• Typically 20 seconds have passed since the

engine starting sequence was completed.

• Engine coolant temperature is more than 76°C.

<4B11>

• Engine coolant temperature is more than 60°C.

<4B12>

• Engine speed is more than 1,188 r/min.

• Volumetric efficiency is more than 30 %.

• Except while fuel is being shut off.

• Monitoring time: 30 seconds.

Judgement Criterion

• Oxygen sensor (front) output voltage does not

get across lean/rich criteria (about 0.5 V) within
about 30 seconds.

FAIL-SAFE AND BACKUP FUNCTION

• None

PROBABLE CAUSES

• Failed oxygen sensor (front)

• Harness damage in oxygen sensor (front) circuit

• Failed injector

• Harness damage in injector circuit

• Exhaust leak

• Air drawn in from gaps in gasket, seal, etc.

• Incorrect fuel pressure

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

• Data list reference table (Refer to

P.13A-155

).

a. Item AC: Oxygen sensor (front)

Q: Is the check result normal?

YES :

Intermittent malfunction (Refer to GROUP

00

− How to Use

Troubleshooting/Inspection Service Points

−

How to Cope with Intermittent Malfunctions
).

NO :

Go to Step 2.

STEP 2. Check for exhaust leaks.

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Repair.

STEP 3. Check for intake system vacuum leak.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair.

STEP 4. Check oxygen sensor (front) itself.

• Oxygen sensor (front) connector check.

• Oxygen sensor (front) check (Refer to

P.13A-186

).

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Repair or replace the connector, or replace
the oxygen sensor (front).

STEP 5. Check injector itself.

• No.1, No.2, No.3, No.4 injector connector check.

• Injector check (Refer to

P.13A-188

).

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Repair or replace the connector, or replace
the injector.

STEP 6. Check harness between oxygen sensor
(front) connector terminal and engine-ECU
connector terminal O2FL.

• Check output line for damage.

Q: Is the check result normal?

YES :

Go to Step 7.

NO :

Repair or replace the connector, or repair
the damaged harness wire.

STEP 7. Check harness between injector
connector and engine-ECU connector.

a. Check and repair harness between No. 1 injector

connector terminal and engine-ECU connector
terminal INJ1.

b. Check and repair harness between No. 2 injector

connector terminal and engine-ECU connector
terminal INJ2.

c. Check and repair harness between No. 3 injector

connector terminal and engine-ECU connector
terminal INJ3.

d. Check and repair harness between No. 4 injector

connector terminal and engine-ECU connector
terminal INJ4.

• Check output line for damage.

Q: Are the check result normal?

YES :

Go to Step 8.

NO :

Repair or replace the connector, or repair
the damaged harness wire.

TROUBLESHOOTING

MULTIPOINT FUEL INJECTION (MPI)

13A-54

STEP 8. Fuel pressure measurement.

• Fuel pressure test (Refer to

P.13A-179

).

Q: Is the check result normal?

YES :

Replace the engine-ECU.

NO :

Repair.

Code No. P0137: Oxygen Sensor (rear) Circuit Low Voltage

OPERATION

• The sensor signal is inputted to the engine-ECU

connector terminal O2RL from the oxygen sensor
(rear) output terminal.

• The oxygen sensor (rear) connector terminal is

earthed with engine-ECU connector terminal
ORLE.

FUNCTION

• The oxygen sensor (rear) converts the concentra-

tion of oxygen in the exhaust emission into a volt-
age and inputs the signal to the engine-ECU.

• When the air-fuel ratio is richer than the theoreti-

cal air-fuel ratio, the oxygen sensor (rear) outputs
a voltage of about 1 V. When it is leaner than the
theoretical air-fuel ratio, it outputs a voltage of
about 0 V.

• In response to the signal, the engine-ECU con-

trols the fuel injection amount so that the air-fuel
ratio can be equivalent to the theoretical air-fuel
ratio.

TROUBLE JUDGMENT

Check Conditions

• Oxygen sensor (rear) offset voltage is more than

0.4 V and is less than 0.6 V.

• Battery positive voltage is more than 11 V and is

less than 16.5 V.

• More than 5 minutes have passed since the

engine starting sequence was completed.

Judgement Criterion

• Oxygen sensor (rear) output voltage is less than

0.2 V for 2 seconds.

FAIL-SAFE AND BACKUP FUNCTION

• None

PROBABLE CAUSES

• Failed oxygen sensor (rear)

• Open/short circuit or harness damage in oxygen

sensor (rear) circuit or loose connector contact

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

• Data list reference table (Refer to

P.13A-155

).

a. Item AD: Oxygen sensor (rear)

Q: Is the check result normal?

YES :

Intermittent malfunction (Refer to GROUP

00

− How to Use

Troubleshooting/Inspection Service Points

−

How to Cope with Intermittent Malfunctions
).

NO :

Go to Step 2.

STEP 2. Perform voltage measurement at oxygen
sensor (rear) connector.

• Disconnect connector, and measure at harness

side.

• Ignition switch: "ON"

• Voltage between terminal engine-ECU ORLE line

and body earth.

OK: 0.4

− 0.6 V

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Go to Step 3.

STEP 3. Check harness between oxygen sensor
(rear) connector terminal and engine-ECU
connector terminal ORLE.

• Check earthing line for open circuit.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair or replace the connector, or repair
the damaged harness wire.

STEP 4. M.U.T.-III data list

• Data list reference table (Refer to

P.13A-155

).

a. Item AD: Oxygen sensor (rear)

Q: Is the check result normal?

YES :

Intermittent malfunction (Refer to GROUP

00

− How to Use

Troubleshooting/Inspection Service Points

−

How to Cope with Intermittent Malfunctions
).

NO :

Replace the engine-ECU.

TROUBLESHOOTING

MULTIPOINT FUEL INJECTION (MPI)

13A-55

STEP 5. Check harness between oxygen sensor
(rear) connector terminal and engine-ECU
connector terminal ORLE.

• Check earthing line for damage.

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Repair or replace the connector, or repair
the damaged harness wire.

STEP 6. Perform voltage measurement at oxygen
sensor (rear) connector.

• Use special tool test harness (MB991658) to con-

nect connector, and measure at pick-up harness.

• Transmission: 2nd speed

• Drive with wide open throttle

• Engine: 3,500 r/min or more

• Voltage between terminal engine-ECU O2RL line

and body earth.

OK:

The output voltage should be 1.1

− 1.5 V.

Q: Is the check result normal?

YES :

Go to Step 8.

NO :

Go to Step 7.

STEP 7. Check oxygen sensor (rear) itself.

• Oxygen sensor check (Refer to

P.13A-186

).

Q: Is the check result normal?

YES :

Repair or replace the connector, or check

intermediate connectors, and repair if
necessary. If intermediate connectors are
normal, check and repair harness between
oxygen sensor (rear) connector terminal
and engine-ECU connector terminal O2RL.

• Check output line for short circuit.

NO :

Replace oxygen sensor (rear).

STEP 8. Check harness between oxygen sensor
(rear) connector terminal and engine-ECU
connector terminal O2RL.

• Check output line for open circuit and damage.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the damaged harness wire.

Code No. P0138: Oxygen Sensor (rear) Circuit High Voltage

OPERATION

• The sensor signal is inputted to the engine-ECU

connector terminal O2RL from the oxygen sensor
(rear) output terminal.

• The oxygen sensor (rear) connector terminal is

earthed with engine-ECU connector terminal
ORLE.

FUNCTION

• The oxygen sensor (rear) converts the concentra-

tion of oxygen in the exhaust emission into a volt-
age and inputs the signal to the engine-ECU.

• When the air-fuel ratio is richer than the theoreti-

cal air-fuel ratio, the oxygen sensor (rear) outputs
a voltage of about 1 V. When it is leaner than the
theoretical air-fuel ratio, it outputs a voltage of
about 0 V.

• In response to the signal, the engine-ECU con-

trols the fuel injection amount so that the air-fuel
ratio can be equivalent to the theoretical air-fuel
ratio.

TROUBLE JUDGMENT

Check Conditions

• More than 2 seconds have passed since the

engine starting sequence was completed.

• Oxygen sensor (rear) offset voltage is more than

0.4 V and is less than 3.8 V.

Judgement Criterion

• Oxygen sensor (rear) output voltage is more than

1.2 V for 2 seconds.

FAIL-SAFE AND BACKUP FUNCTION

• None

PROBABLE CAUSES

• Failed oxygen sensor (rear)

• Short circuit in oxygen sensor (rear) circuit or

loose connector contact

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

• Data list reference table (Refer to

P.13A-155

).

a. Item AD: Oxygen sensor (rear)

Q: Are the check results normal?

TROUBLESHOOTING

MULTIPOINT FUEL INJECTION (MPI)

13A-56

YES :

Intermittent malfunction (Refer to GROUP

00

− How to Use

Troubleshooting/Inspection Service Points

−

How to Cope with Intermittent Malfunctions
).

NO :

Go to Step 2.

STEP 2. Check harness between oxygen sensor
(rear) connector terminal and engine-ECU
connector terminal O2RL.

• Check output line for short circuit.

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Repair or replace the connector, or repair
the damaged harness wire.

STEP 3. Check harness between oxygen sensor
(rear) connector terminal and engine-ECU
connector terminal ORLE.

• Check earthing line for short circuit.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair or replace the connector, or repair
the damaged harness wire.

STEP 4. M.U.T.-III data list

• Data list reference table (Refer to

P.13A-155

).

a. Item AD: Oxygen sensor (rear)

Q: Is the check result normal?

YES :

Intermittent malfunction (Refer to GROUP

00

− How to Use

Troubleshooting/Inspection Service Points

−

How to Cope with Intermittent Malfunctions
).

NO :

Replace the engine-ECU.

Code No. P0171: Abnormal Fuel System (lean)

OPERATION

• Check code No. P0261: No. 1 injector circuit low

input (Refer to

P.13A-62

).

• Check code No. P0262: No. 1 injector circuit high

input (Refer to

P.13A-63

).

• Check code No. P0264: No. 2 injector circuit low

input (Refer to

P.13A-64

).

• Check code No. P0265: No. 2 injector circuit high

input (Refer to

P.13A-65

).

• Check code No. P0267: No. 3 injector circuit low

input (Refer to

P.13A-66

).

• Check code No. P0268: No. 3 injector circuit high

input (Refer to

P.13A-67

).

• Check code No. P0270: No. 4 injector circuit low

input (Refer to

P.13A-68

).

• Check code No. P0271: No. 4 injector circuit high

input (Refer to

P.13A-69

).

FUNCTION

• If the fuel system goes out of order, the fuel cor-

rection value will become larger.

• The engine-ECU checks whether the fuel trim

value is within a specified range.

TROUBLE JUDGMENT

Check Conditions

• Engine coolant temperature is less than 100°C

when the engine is started.

• Intake air temperature is less than 60°C when the

engine is started.

• Under the closed loop air/fuel ratio control.

• Engine coolant temperature is more than 76°C.

• Air flow sensor output is more than 6.4 g/sec.

Judgement Criterion

• Long-term fuel trim is more than +12.5 % for 5

seconds.

or

• Short-term fuel trim is more than +7.0 % for 5

seconds. <4B11>

• Short-term fuel trim is more than +10.0 % for 5

seconds. <4B12>

Check Conditions

• Engine coolant temperature is more than 100°C

when the engine is started.

• Intake air temperature is more than 60°C when

the engine is started.

• Under the closed loop air/fuel ratio control.

• Engine coolant temperature is more than 76°C.

• Air flow sensor output is more than 6.4 g/sec.

Judgement Criterion

• Long-term fuel trim is more than +12.5 % for 5

seconds.

or

• Short-term fuel trim is more than +17.2 % for 5

seconds. <4B11>