Mitsubishi Outlander GS45X. Manual — part 790

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

13B-93

.

CIRCUIT OPERATION

• Power is supplied from the MFI relay (terminal

No. 2) to the left bank heated oxygen sensor
(front) heater.

• The ECM (terminal No. 34) controls continuity to

the left bank heated oxygen sensor (front) heater
by turning the power transistor in the ECM "ON"
and "OFF".

.

TECHNICAL DESCRIPTION

• The ECM checks whether the heater current is

within a specified range when the heater is ener-
gized.

• The ECM checks whether the heater voltage is

within a specified range when the heater is not
energized.

.

DESCRIPTIONS OF MONITOR METHODS

Left bank heated oxygen sensor heater (front) cur-

rent or voltage is out of specified range.

.

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)

• Not applicable

.

AK700399AB

MFI relay

A-33X

Connector: A-33X

AK700404

Left bank heated oxygen
sensor (front)

Connector: B-14

AB

B-14 (B)

AK700401AB

ECM

B-10 (GR)

Connector: B-10

AK900602

Connector: A-13

A-13

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

13B-94

DTC SET CONDITION

Logic Flow Chart

.

Check Conditions

• More than 2 seconds have passed since the

engine starting sequence was completed.

• While the left bank heated oxygen sensor (front)

heater is on.

• Battery positive voltage is at between 11 and 16.5

volts.

Judgement Criterion

• The left bank heated oxygen sensor (front) heater

current has continued to be lower than 0.17
ampere for 2 seconds.

.

Check Conditions

• More than 2 seconds have passed since the

engine starting sequence was completed.

• While the left bank heated oxygen sensor (front)

heater is off.

• Battery positive voltage is at between 11 and 16.5

volts.

Judgement Criterion

• The left bank heated oxygen sensor (front) heater

voltage has continued to be lower than 2.0 volts
for 2 seconds.

.

End

No

No

Malfunction

Good

Current < 0.17A

or

Current > 10.5A

Voltage < 2.0V

AK900352

Heater activation
command ON

No

No

Start

Yes

Yes

Yes

Yes

Yes

No

Continuous
failure for 2secs

Monitoring
conditions

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

13B-95

OBD-II DRIVE CYCLE PATTERN

Refer to Diagnostic Function

− OBD-II Drive Cycle −

Pattern 2

P.13B-11

.

.

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

• Left bank heated oxygen sensor (front) heater.

• Connector damage.

• Harness damage

• ECM failed.

DIAGNOSIS

Required Special Tools:

• MD998464: Test Harness

STEP 1. Check harness connector B-14 at the left bank
heated oxygen sensor (front) and harness connector B-10
at the ECM for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 2.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 6.

STEP 2. Check the left bank heated oxygen sensor (front).
(1) Disconnect left bank heated oxygen sensor (front)

connector B-14 and connect test harness special tool,
MD998464, to the connector on the left bank heated oxygen
(front) sensor side.

(2) Measure the resistance between heated oxygen sensor

connector terminal No. 1 (red clip) and terminal No. 3 (blue
clip).

Standard value: 4.5

− 8.0 Ω [at 20°C (68°F)]

Q: Is the measured resistance between 4.5 and 8.0 ohms

[at 20

°C (68°F)]?

YES : Go to Step 3.
NO : Replace the left bank heated oxygen sensor (front).

Then go to Step 6.

STEP 3. Measure the power supply voltage at left bank
heated oxygen sensor (front) harness side connector B-14.
(1) Disconnect the connector B-14 and measure at the harness

side.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal No. 1 and ground.

• Voltage should be battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is battery positive voltage (approximately 12 volts)

present?
YES : Go to Step 4.
NO : Repair harness wire between the MFI relay connector

A-33X (terminal No. 2) and the left bank heated
oxygen sensor (front) connector B-14 (terminal No. 1)
because of open circuit or harness damage. Then go
to step 6.

AK700179

MD998464

Red

Blue

AB

Heated
oxygent
sensor
component
side
connector

1

2

3

4

AK700186 AB

B-14 harness
connector:
component side

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

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STEP 4.Check for open circuit to ground or harness
damage between left bank heated oxygen sensor (front)
connector B-14 and ECM connector B-10 (terminal No.
125).
(1) Disconnect the left bank heated oxygen sensor (front)

connector B-14 and ECM connector B-10.

(2) Measure the resistance between heated oxygen sensor

connector B-14 (terminal No. 3) and the ECM connector
B-10 (terminal No. 34).

• Should be less than 2 ohms.

(3) Check for the continuity between the oxygen sensor

connector B-14 (terminal No. 3) and ground.

• Not continuity.

Q: Is the harness wire in good condition?

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

STEP 5. Check the trouble symptoms.
(1) Carry out a test drive with the drive cycle pattern. Refer to

Diagnostic Function

− OBD-II Drive Cycle − Pattern 2

P.13B-11

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0051 set?

YES : Replace the ECM. When the ECM is replaced,

register the ID code. Refer to GROUP 42B, Diagnosis
− ID Codes Registration Judgment Table <Vehicles

with KOS>

P.42B-15

or GROUP 42C, Diagnosis

− ID

Codes Registration Judgment Table <Vehicles with
WCM>

P.42C-10

. Then go to Step 6.

NO : 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.00-15

.

AK700187

1

2

3

4

16 15 14 13 12 11 10 9 8 7 6 5 4 3

2

1

32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17

48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33

64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49

B-14 harness connector:
component side

B-10 harness connector:
component side

AB

AK703867

1

2

3

4

AB

B-14 harness
connector:
component side