Mitsubishi Montero (2004+). Manual — part 362

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-935

• Improper connector contact, open circuit or

short-circuited harness wire.

• Malfunction of the PCM.

DIAGNOSIS

STEP 1. Check the ignition coil.
Refer to GROUP 16, Ignition System

− On-vehicle service −

Ignition Coil Check

P.16-31

.

Q: Are there any abnormalities?

YES : Replace the ignition coil. Then confirm that the

malfunction symptom is eliminated.

NO : Go to Step 2.

STEP 2. Check harness connectors B-31, B-32, B-34 at
ignition coil for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 3.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then confirm that the

malfunction symptom is eliminated.

STEP 3. Measure the power supply voltage at ignition coil
connectors B-31, B-32, B-34.
(1) Disconnect the connector B-31, B-32, B-34 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.

AK201291

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B-31(GR)

B-32(GR)

B-34(GR)

AB

CONNECTORS: B-31, B-32, B-34

HARNESS
CONNECTOR:
COMPONENT SIDE

AK201291

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2

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B-31(GR)

B-32(GR)

B-34(GR)

AB

CONNECTORS: B-31, B-32, B-34

HARNESS
CONNECTOR:
COMPONENT SIDE

AK000414AL

B-31, B-32, B-34 HARNESS
CONNECTORS:
COMPONENT SIDE

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MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-936

NO : Check the connectors D-208, D-221, E-111 at

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

P.00E-2

. If intermediate

connector are in good condition, repair harness wire
between ignition switch connector D-204 (terminal
No. 2) and ignition coil connector B-31, B-32, B-34
(terminal No. 1) because of open circuit. Then confirm
that the malfunction symptom is eliminated.

STEP 4. Check the circuit at ignition coil harness side
connectors B-31, B-32, B-34.
(1) Disconnect the connectors B-31, B-32, B-34 and measure

at the harness side.

(2) Engine cranking.

(3) Measure the voltage between terminal No. 3 and ground.

• Voltage should measure 0.3 and 3.0 volts.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage between 0.3 and 3.0 volts?

YES : Go to Step 7.
NO : Go to Step 5.

STEP 5. Check connector D-133 at PCM 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 confirm that the

malfunction symptom is eliminated.

AK201291

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B-31(GR)

B-32(GR)

B-34(GR)

AB

CONNECTORS: B-31, B-32, B-34

HARNESS
CONNECTOR:
COMPONENT SIDE

AK000415 AM

B-31, B-32, B-34 HARNESS
CONNECTORS:
COMPONENT SIDE

1

2

3

AK200939

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AB

CONNECTOR: D-133

HARNESS CONNECTOR:
COMPONENT SIDE

PCM

D-133(GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-937

STEP 6. Check for open circuit and short circuit to ground
between ignition coil connector and PCM connector.

a. Check the harness wire between ignition coil connector

B-32 (terminal No. 3) and PCM connector D-133 (terminal
No. 31) at ignition coil 1.

b. Check the harness wire between ignition coil connector

B-34 (terminal No. 3) and PCM connector D-133 (terminal
No. 35) at ignition coil 2.

c. Check the harness wire between ignition coil connector

B-31 (terminal No. 3) and PCM connector D-133 (terminal
No. 44) at ignition coil 3.

Q: Is the harness wire in good condition?

YES : Replace the PCM. Then confirm that the malfunction

symptom is eliminated.

NO : Repair it. Then confirm that the malfunction symptom

is eliminated.

AK201291

1

2

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B-31(GR)

B-32(GR)

B-34(GR)

AB

CONNECTORS: B-31, B-32, B-34

HARNESS
CONNECTOR:
COMPONENT SIDE

AK200939

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AB

CONNECTOR: D-133

HARNESS CONNECTOR:
COMPONENT SIDE

PCM

D-133(GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-938

STEP 7. Check for harness damage between ignition coil
connector and PCM connector.

a. Check the harness wire between ignition coil connector

B-32 (terminal No. 3) and PCM connector D-133 (terminal
No. 31) at ignition coil 1.

b. Check the harness wire between ignition coil connector

B-34 (terminal No. 3) and PCM connector D-133 (terminal
No. 35) at ignition coil 2.

c. Check the harness wire between ignition coil connector

B-31 (terminal No. 3) and PCM connector D-133 (terminal
No. 44) at ignition coil 3.

Q: Is the harness wire in good condition?

YES : Go to Step 8.
NO : Repair it. Then confirm that the malfunction symptom

is eliminated.

STEP 8. Check for continuity at ignition coil harness side
connectors B-31, B-32, B-34.
(1) Disconnect the connectors B-31, B-32, B-34 and measure

at the harness side.

(2) Check for continuity between terminal No. 2 and ground.

• Should be less than 2 ohms.

Q: Does continuity exist?

YES : Go to Step 9.
NO : Repair harness wire between ignition coil connectors

B-31, B-32, B-34 (terminal No. 2) and ground
because of open circuit or harness damage. Then
confirm that the malfunction symptom is eliminated.

AK201291

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2

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B-31(GR)

B-32(GR)

B-34(GR)

AB

CONNECTORS: B-31, B-32, B-34

HARNESS
CONNECTOR:
COMPONENT SIDE

AK200939

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CONNECTOR: D-133

HARNESS CONNECTOR:
COMPONENT SIDE

PCM

D-133(GR)

AK201291

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B-31(GR)

B-32(GR)

B-34(GR)

AB

CONNECTORS: B-31, B-32, B-34

HARNESS
CONNECTOR:
COMPONENT SIDE

AK101265

1

2

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AL

B-31, B-32, B-34 HARNESS
CONNECTORS:
COMPONENT SIDE