Mitsubishi Montero (2004+). Manual - part 363

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-939

STEP 9. Check connector B-25X at engine speed detection 
and connector D-134 at PCM for damage.
Q: Is the connector in good condition?

YES : Go to Step 10.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then confirm that the 

malfunction symptom is eliminated.

AK200979

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AB

B-25X

HARNESS 
CONNECTOR: 
COMPONENT SIDE

CONNECTOR: B-25X

AK201166

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CONNECTOR: D-134

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PCM

D-134(GR)

HARNESS CONNECTOR: 
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-940

STEP 10. Check for open circuit and short circuit to 
ground and harness damage between engine speed 
detection connector B-25X and PCM connector D-134 
(terminal No. 87).
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.

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AB

B-25X

HARNESS 
CONNECTOR: 
COMPONENT SIDE

CONNECTOR: B-25X

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CONNECTOR: D-134

AB

PCM

D-134(GR)

HARNESS CONNECTOR: 
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-941

INSPECTION PROCEDURE 32: A/C system.

.

COMMENT

• When the A/C is "ON", the battery positive volt-

age is applied on the PCM (terminal No. 69) from 
the A/C belt lock-ECU. 
When battery positive voltage is applied to the 
PCM, the PCM turns "ON" the power transistor in 
the PCM. The PCM delays A/C engagement 
momentarily while it increases idle rpm. Then the 
A/C compressor clutch relay coil will be ener-
gized. 

With this, the A/C compressor clutch relay turns 
"ON", and the A/C compressor clutch operates.

.

TROUBLESHOOTING HINTS (The most likely 
causes for this case: )

• Malfunction of the A/C control system.

• Malfunction of the A/C switch.

• Improper connector contact, open circuit or 

short-circuited harness wire.

• Malfunction of the PCM.

GREEN-RED

ORANGE

AK302914

8

POWERTRAIN CONTROL MODULE (PCM)

AUTOMATIC
COMPRESSOR
CONTROLLER *

2

A/C COMPRESSOR
RELAY

69

A/C-ECU *

1

*

1 

: AUTOMATIC A/C SYSTEM

*

2 

: MANUAL A/C SYSTEM

A/C Circuit

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21 22

232425

2627

10111213

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19

D-132

(MU803802)

61
656667686970 717273
74757677787980 8182
8384

858687

8889

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6364

D-134

(MU803804)

AK201038AJ

CONNECTORS: D-132, D-134

PCM

D-134(GR)

D-132(GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-942

DIAGNOSIS

STEP 1. Check harness connector D-132, D-134 at PCM 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 confirm that the 

malfunction symptom is eliminated.

STEP 2. Check the circuit at PCM connector D-132.
(1) Disconnect the connectors D-132 and measure at the 

harness side.

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

(3) Measure the voltage between terminal No. 8 and ground.

• Voltage should be battery positive voltage.

(4) Using a jumper wire, connect terminal No. 8 to ground.

• A/C compressor relay should turn "ON".

(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the voltage and A/C compressor relay condition 

normal?
YES : Go to Step 3.
NO :  Refer to GROUP 55, Diagnosis 

− Introduction To 

Heater, Air Conditioning And Ventilation Diagnosis 

P.55A-5

. Then confirm that the malfunction symptom 

is eliminated.

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CONNECTORS: D-132, D-134

PCM

D-134(GR)

D-132(GR)

AB

D-132 HARNESS CONNECTOR: 
COMPONENT SIDE

D-134 HARNESS CONNECTOR: 
COMPONENT SIDE

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CONNECTOR: D-132

HARNESS CONNECTOR: 
COMPONENT SIDE

PCM

D-132(GR)

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D-132 HARNESS 
CONNECTOR: 
COMPONENT SIDE

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