Mitsubishi Montero Sport (2004+). Manual — part 356

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-837

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. 83) from
the A/C compressor-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 r/min. 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 functions.

.

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.

BL

ACK

-YELL

OW

GREEN-

YELL

OW

AK303790

A/C Circuit

20

POWERTRAIN CONTROL MODULE(PCM)

AUTOMATIC
COMPRESSOR-ECU

A/C COMPRESSOR
CLUTCH RELAY

83

10

2

3 4

5 6

7 8

9

11 12 13 14 15 16 17 18 19 20

30

21 22 23

24

25

26 27 28 29

31 32 33

34 35

1

C-89
(MU803784)

71

76

77

72 73 74

75

79 80

78

81

87 88

89

91

90

92

97

98

82

93

83

94

84 85

95

86

96

C-91
(MU803782)

AK103738AG

CONNECTORS: C-89, C-91

PCM

C-89(GR) C-91(GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-838

DIAGNOSIS

STEP 1. Check harness connector C-89, C-91 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 C-89.
(1) Disconnect the connectors C-89 and measure at the

harness side.

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

(3) Measure the voltage between terminal No. 20 and ground.

• Voltage should be battery positive voltage.

(4) Using a jumper wire, connect terminal No. 20 to ground.

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

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

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

− Introduction To

Heater, Air Conditioning And Ventilation Diagnosis

P.55-5

. Then confirm that the malfunction symptom is

eliminated.

AK200055

98

78

71

88

89

76

77

72
79
91

73
80

74

75

81
92

82

83

93

84

85

94

86

87

95

96

90

97

2

3

4

5

6

7

8

9

11

12

13

14

15

16

17

18

19

20

30

21

22

23

24

25

26

27

28

29

31

32

33

34

35

1

10

AB

98

78

71

88

89

76

77

72
79
91

73
80

74

75

81
92

82

83

93

84

85

94

86

87

95

96

90

97

2

3

4

5

6

7

8

9

11

12

13

14

15

16

17

18

19

20

30

21

22

23

24

25

26

27

28

29

31

32

33

34

35

1

10

CONNECTORS: C-89, C-91

C-89(GR) C-91(GR)

C-89 HARNESS CONNECTOR:
COMPONENT SIDE

C-91 HARNESS CONNECTOR:
COMPONENT SIDE

AK103914

2

3

4

5

6

7

8

9

11

12

13

14

15

16

17

18

19

20

30

21

22

23

24

25

26

27

28

29

31

32

33

34

35

1

10

AB

CONNECTOR: C-89

C-89(GR)

HARNESS CONNECTOR:
COMPONENT SIDE

AKX01448

13

14

15

27

12

26

11 10

25

9

24

28

16

17

29

30

18

31

19

20

32

33

21

22

23

6 5

4 3

2

1

7

8

34

35

C-89 HARNESS CONNECTOR:
COMPONENT SIDE

AT

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-839

STEP 3. Check the circuit at PCM connector C-91.
(1) Disconnect the connectors C-91 and measure at the

harness side.

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

(3) Measure the voltage between terminal No. 83 and ground.

• Voltage should be 1 volt or less when the A/C switch is

"OFF".

• Voltage should be battery positive voltage when the A/C

switch is "ON".

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage within the specified range?

YES : Replace the PCM. Then confirm that the malfunction

symptom is eliminated.

NO : Refer to GROUP 55, Diagnosis

− Introduction To

Heater, Air Conditioning And Ventilation Diagnosis

P.55-5

.

DATA LIST REFERENCE TABLE

M1131152000917

CAUTION

• When shifting the selector lever to D range, the brakes should be applied so that the vehicle does

not move forward.

• Driving tests always need two persons: one driver and one observer.

NOTE: Sensor 1 indicates the sensor mounted at a position closest to the engine, and sensor 2 indicates the
sensor mounted at the position second close to the engine.
NOTE: Bank 1 indicates the right bank cylinder, and bank 2 indicates the left bank cylinder
NOTE: *

1

: In a new vehicle [driven approximately 500 km (311 mile) or less], the volume airflow sensor output

frequency is sometimes 10% higher than the standard frequency.
NOTE: *

2

: If the idle speed is lower than the standard value on a very cold engine [approximately

−

20

°

C

(

−

4

°

F] even when the IAC motor is fully opened, the air volume limiter built in the throttle body could be defec-

tive.
NOTE: *

3

: The injector drive time represents the time when the cranking speed is at 250 r/min or below when

the power supply voltage is 11 volts.
NOTE: *

4

: In a new vehicle [driven approximately 500 km (311 mile) or less], the injector drive time is some-

times 10% longer than the standard time.
NOTE: *

5

: In a new vehicle [driven approximately 500 km (311 mile) or less], the step of the stepper motor is

sometimes 30 steps greater than the standard value.
NOTE:

*6

: Applicable to GST

NOTE:

*7

: Vehicles for Canada, the headlight, taillight, etc. remain lit even when the lighting switch is in "OFF"

position but this is no problem for checks.

AK104028

98

78

71

88

89

76

77

72
79
91

73
80

74

75

81
92

82

83

93

84

85

94

86

87

95

96

90

97

AB

CONNECTOR: C-91

C-91(GR)

HARNESS CONNECTOR:
COMPONENT SIDE

AKX01449

71

72

73

74

78
90

79
91

80

81
92

8584
95

86
96

75
87

76
88
97

77
89
98

82
93

83
94

C-91 HARNESS CONNECTOR:
COMPONENT SIDE

AT

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-840

MUT-III
SCAN
TOOL
DISPLAY

ITEM
NO.

INSPECTION
ITEM

INSPECTION REQUIREMENT

NORMAL
CONDITION

INSPECTION
PROCEDURE
NO.

REFERENCE
PAGE

A/C
RELAY

49

A/C
compressor
clutch relay

Engine: warming up, idling

OFF

Procedure
No. 32

P.13A-837

Engine:
warming up,
idling

A/C
compressor
clutch is not
operating

OFF

A/C
compressor
clutch is
operating

ON

A/C
SWITCH

28

A/C switch

Engine: warming up, idling

OFF

Procedure
No. 32

P.13A-837

Engine:
warming up,
idling

A/C
compressor
clutch is not
operating

OFF

A/C
compressor
clutch is
operating

ON

BARO
SENSOR

25

Barometric
pressure
sensor

Ignition switch:
"ON"

At altitude of 0
m (0 ft)

101 kPa
(29.8
in.Hg)

Code
No.P2227,
P2228,
P2229

P.13A-684

,

P.13A-692

,

P.13A-707

At altitude of
600 m (1,969
ft)

95 kPa
(28.1
in.Hg)

At altitude of
1,200 m
(3,937 ft)

88 kPa
(26.0
in.Hg)

At altitude of
1,800 m
(5,906 ft)

81 kPa
(23.9
in.Hg)

BATT
VOLTAGE

16

Battery
voltage (power
supply)

Ignition switch: "ON"

Battery
positive
voltage

Procedure
No. 28

P.13A-804