Mitsubishi Montero (2004+). Manual - part 313

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-739

STEP 5. Check for harness damage between accelerator 
pedal position sensor connector D-138 (terminal No. 1) and 
PCM connector D-135 (terminal No. 91).
Q: Is the harness wire in good condition?

YES : Go to Step 6.
NO :  Repair it. Then go to Step 11.

STEP 6. Using scan tool MB991958, read the diagnostic 
trouble code (DTC).

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK"(OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) After the DTC has been deleted, read the DTC again.
(4) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is DTC P2121 set?

YES : Replace the PCM. Then go to Step 11.
NO :  It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection. Service Points 

P.00-6

.

AK200945

3

4

5

1

2

8

6

7

AB

CONNECTOR: D-138

HARNESS 
CONNECTOR: 
COMPONENT SIDE

D-138(GR)

AK200947

91

92

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119

120

CONNECTOR: D-135

HARNESS CONNECTOR: 
COMPONENT SIDE

AB

PCM

D-135(GR)

AK302970

AB

MB991911

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-740

STEP 7. Check the accelerator pedal position switch.
(1) Disconnect the accelerator pedal position switch connector 

D-138.

(2) Check the continuity between accelerator pedal position 

switch side connector terminal No. 4 and No. 5.

Standard value:

Continuity (foot released from accelerator pedal)
Non-continuity (accelerator pedal depressed)

Q: Is the switch operating properly?

YES : Go to Step 8.
NO :  Replace the accelerator pedal position sensor. Then 

go to Step 11.

STEP 8. Check connector D-133 at PCM for damage.
Q: Is the connector in good condition?

YES : Go to Step 9.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 11.

AK200945

3

4

5

1

2

8

6

7

AB

CONNECTOR: D-138

HARNESS 
CONNECTOR: 
COMPONENT SIDE

D-138(GR)

6 7 8

1 2 3 4 5

AK201453AB

ACCELERATOR PEDAL
POSITION SWITCH
SIDE CONNECTOR

AK200939

31

32

33

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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-741

STEP 9. Check for short circuit to ground between 
accelerator pedal position switch connector D-138 
(terminal No. 4) and PCM connector D-133 (terminal No. 
38).
Q: Is the harness wire in good condition?

YES : Go to Step 10.
NO :  Repair it. Then go to Step 11.

AK200945

3

4

5

1

2

8

6

7

AB

CONNECTOR: D-138

HARNESS 
CONNECTOR: 
COMPONENT SIDE

D-138(GR)

AK200939

31

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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-742

STEP 10. Using scan tool MB991958, read the diagnostic 
trouble code (DTC).

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK"(OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) After the DTC has been deleted, read the DTC again.
(4) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is DTC P2121 set?

YES : Replace the PCM. Then go to Step 11.
NO :  It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection. Service Points 

P.00-6

.

STEP 11. Using scan tool MB991958, read the diagnostic 
trouble code (DTC).
(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) After the DTC has been deleted, read the DTC again.
(4) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is DTC P2121 set?

YES : Retry the troubleshooting.
NO :  The inspection is complete.

AK302970

AB

MB991911

MB991824

MB991827

AK302970

AB

MB991911

MB991824

MB991827