Mitsubishi Montero (2004+). Manual — part 356

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-911

STEP 2. Check the MFI relay.
(1) Remove the MFI relay.

(2) Check for continuity between the MFI relay terminal No. 2

and No. 4.

• There should be continuity (approximately 70 ohms)

(3) Use jumper wires to connect MFI relay terminal No. 2 to the

positive battery terminal and terminal No. 4 to the negative
battery terminal.

(4) Check the continuity between the MFI relay terminal No. 1

and No. 3 while connecting and disconnecting the jumper
wire at the negative battery terminal.

• Should be less than 2 ohms. (Negative battery terminal

connected)

• Should be open loop. (Negative battery terminal discon-

nected)

(5) Install the MFI relay.
Q: Is the resistance normal?

YES : Go to Step 3.
NO : Replace the MFI relay. Then confirm that the

malfunction symptom is eliminated.

AK200951

2 1

3

4

B-22X

AB

CONNECTOR: B-22X

HARNESS
CONNECTOR:
COMPONENT SIDE

1

2

3

4

AK201380AE

MFI RELAY SIDE
CONNECTOR

1

2

3

4

AK201381AE

MFI RELAY SIDE
CONNECTOR

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-912

STEP 3. Measure the power supply voltage at MFI relay
harness side connector B-22X.
(1) Disconnect the connector B-22X and measure at the

harness side.

(2) Measure the voltage between terminal No. 2, No. 3 and

ground.

• Voltage should be battery positive voltage.

Q: Is battery positive voltage (approximately 12 volts)

present?
YES : Go to Step 4.
NO : Check harness connector A-03 at intermediate

connector for damage, and repair or replace as
required. Refer to GROUP 00E, Harness Connector
Inspection

P.00E-2

. If intermediate connector A-03 is

in good condition, repair an open circuit between
fusible link (5) and MFI relay connector B-22X
(terminal No. 2, No. 3). Then confirm that the
malfunction symptom is eliminated.

STEP 4. Check harness connector D-133 at PCM for
damage.
Q: Is the harness 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 confirm that the

malfunction symptom is eliminated.

AK200951

2 1

3

4

B-22X

AB

CONNECTOR: B-22X

HARNESS
CONNECTOR:
COMPONENT SIDE

2 1

3

4

AK201382AE

B-22X HARNESS
CONNECTOR:
COMPONENT SIDE

AK200939

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58

50

51

AB

CONNECTOR: D-133

HARNESS CONNECTOR:
COMPONENT SIDE

PCM

D-133(GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-913

STEP 5. Measure the ignition switch-IG signal voltage at
PCM harness side connector D-133.
(1) Disconnect the connector D-133 and measure at the

harness side.

(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal No. 50 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 6.
NO : Check harness connector E-111, D-02, D-28 at

intermediate connector for damage, and repair or
replace as required. Refer to GROUP 00E, Harness
Connector Inspection

P.00E-2

. If intermediate

connector E-111, D-02, D-28 are in good condition,
repair it because of open circuit between ignition
switch connector D-204 (terminal No. 2) and PCM
connector D-133 (terminal No. 50). Then confirm that
the malfunction symptom is eliminated.

AK200939

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58

50

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AB

CONNECTOR: D-133

HARNESS CONNECTOR:
COMPONENT SIDE

PCM

D-133(GR)

AK201375

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D-133 HARNESS
CONNECTOR:
COMPONENT SIDE

AK201375AB

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MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-914

STEP 6. Measure the backup power supply voltage at PCM
harness side connector D-133.
(1) Disconnect the connector D-133 and measure at the

harness side.

(2) Measure the voltage between terminal No.58 and ground.

• Voltage should be battery positive voltage.

Q: Is battery positive voltage (approximately 12 volts)

present?
YES : Go to Step 7.
NO : Check harness connector A-03 at intermediate

connector for damage, and repair or replace as
required. Refer to GROUP 00E, Harness Connector
Inspection

P.00E-2

. If intermediate connector A-03 is

in good condition, repair an open circuit between
fusible link (5) and PCM connector D-133 (terminal
No. 58). Then confirm that the malfunction symptom
is eliminated.

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AB

CONNECTOR: D-133

HARNESS CONNECTOR:
COMPONENT SIDE

PCM

D-133(GR)

AK201376

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D-133 HARNESS
CONNECTOR:
COMPONENT SIDE

AK201376AB

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