Mitsubishi Montero (2004+). Manual - part 329

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-803

TECHNICAL DESCRIPTION

• The barometric pressure sensor outputs a volt-

age which corresponds to the barometric pres-
sure.

• The PCM checks whether this voltage is within a 

specified range.

.

DESCRIPTIONS OF MONITOR METHODS
Barometric pressure sensor output voltage does not 

change for specified period. (approximately 1 
week)

.

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)

• Throttle position sensor

.

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• Barometric pressure is lower than 76 kPa (22.4 

in.Hg).

Judgement Criteria

• During 15 times of driving, the changes in the 

sensor output voltage should be 0.015 volt 
[equivalent to 0.4 kPa (0.12 in.Hg)] or less.

START

MONITORING

CONDITIONS

END

NO

NO

NO

YES

YES

YES

MALFUNCTION

GOOD

OUTPUT VOLTAGE

CHANGE

15 WARM-UP CYCLES

HAVE PASSED

AK302968

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-804

• Make sure that the engine coolant temperature is 

72

°C (160°F) or higher during each of the 15 

times of driving. Also, during each of the 15 times 
of driving, make sure that after the engine has 
been started, the engine coolant temperature has 
increased to 23

°C (40°F) or higher.

.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function 

− OBD-II Drive Cycle − 

Procedure 6 

− Other Monitor 

P.13A-4

.

.

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

• Barometric pressure sensor failed.

• Open barometric pressure sensor circuit, harness 

damage, or connector damage.

• PCM failed.

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

STEP 1. 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) Read the DTC.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC P2228 set?

YES : Refer to, DTC P2228 

− Barometric Pressure Circuit 

Low Input 

P.13A-808

.

NO :  Go to Step 2.

STEP 2. Check connector B-48 at the barometric pressure 
sensor for damage.
Q: Is the 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 go to Step 9. 

AK302970

AB

MB991911

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-805

STEP 3. Check the continuity at barometric pressure 
sensor harness side connector B-48.

(1) Disconnect the connector B-48 and measure at the harness 

side.

(2) Check for the continuity between terminal No. 5 and 

ground.

• Should be less than 2 ohms.

Q: Does continuity exist?

YES : Go to Step 6.
NO :  Go to Step 4.

STEP 4. Check connector D-134 at PCM for damage.
Q: Is the 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 go to Step 9.

AK200937

3

4

5

1

2

6

7

AB

HARNESS 
CONNECTOR: 
COMPONENT SIDE

CONNECTOR: B-48

B-48(B)

AKX01409

1

2

3

4

5

6

7

B-48 HARNESS CONNECTOR: 
COMPONENT SIDE

AL

AK201166

61

62

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64

65

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68

69

70

71

76

77

78

79

85

86

87

80

72

73

74

75

81

82

83

84

88

89

CONNECTOR: D-134

AB

PCM

D-134(GR)

HARNESS CONNECTOR: 
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-806

STEP 5. Check for open circuit and harness damage 
between barometric pressure sensor connector B-48 
(terminal No. 5) and PCM connector D-134 (terminal No. 
88).
Q: Is the harness wire in good condition?

YES : Replace the PCM. Then go to Step 9 
NO :  Repair it. Then go to Step 9.

STEP 6. Check connector D-134 at PCM for damage.
Q: Is the connector in good condition?

YES : Go to Step 7.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 9.

AK200937

3

4

5

1

2

6

7

AB

HARNESS 
CONNECTOR: 
COMPONENT SIDE

CONNECTOR: B-48

B-48(B)

AK201166

61

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64

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66

67

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69

70

71

76

77

78

79

85

86

87

80

72

73

74

75

81

82

83

84

88

89

CONNECTOR: D-134

AB

PCM

D-134(GR)

HARNESS CONNECTOR: 
COMPONENT SIDE

AK201166

61

62

63

64

65

66

67

68

69

70

71

76

77

78

79

85

86

87

80

72

73

74

75

81

82

83

84

88

89

CONNECTOR: D-134

AB

PCM

D-134(GR)

HARNESS CONNECTOR: 
COMPONENT SIDE