Mitsubishi Grandis. Manual — part 781

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-375

106

Power supply
voltage applied to
throttle position
sensor

Ignition switch: ON

4.9

− 5.1 V

107

Accelerator pedal
position sensor (sub)

Ignition switch: ON

Release the
accelerator pedal

0.4

− 1.0 V

Depress the
accelerator pedal fully

3.6 V or more

108

Cylinder 2,3 oxygen
sensor (front)

Engine: Running at 2,500 r/min after warmed
up

0.4 V or less

⇔ 0.6 − 1.0 V

(Changes repeatedly)

109

Cylinder 1,4 oxygen
sensor (front)

Engine: Running at 2,500 r/min after warmed
up

0.4 V or less

⇔ 0.6 − 1.0 V

(Changes repeatedly)

113

Throttle position
sensor (sub)

• Remove the intake

air hose at the
throttle body

• Disconnect the

throttle position
sensor, and then
connect terminal
numbers No. 3,
No. 4, No. 5 and
No. 6 with the use
of the special tool
(MB991658).

• Ignition switch: ON

Fully close the throttle
valve with your finger

2.2

− 2.8 V

Fully open the throttle
valve with your finger

4.0 V or more

114

Accelerator pedal
position sensor
(main)

Ignition switch: ON

Release the
accelerator pedal

0.9

− 1.2 V

Depress the
accelerator pedal fully

4.0 V or more

115

Throttle position
sensor (main)

• Remove the intake

air hose at the
throttle body

• Disconnect the

throttle position
sensor, and then
connect terminal
numbers No. 3,
No. 4, No. 5 and
No. 6 with the use
of the special tool
(MB991658).

• Ignition switch:

"ON"

Fully close the throttle
valve with your finger

0.3

− 0.7 V

Fully open the throttle
valve with your finger

4.0 V or more

116

Cylinder 2,3 oxygen
sensor (rear)

Engine: Idling after warmed up (Check using
a digital type voltmeter)

0.4 V or less

⇔ 0.6 − 1.0 V

(Changes repeatedly)

117

Cylinder 1,4 oxygen
sensor (rear)

Engine: Idling after warmed up (Check using
a digital type voltmeter)

0.4 V or less

⇔ 0.6 − 1.0 V

(Changes repeatedly)

Terminal
No.

Check item

Check condition (Engine condition)

Normal condition

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-376

NOTE: * :The average voltage is shown when an
analog voltmeter is used (because the average
voltage might not be shown stably when digital
voltmeter is used).

CHECK CHART FOR RESISTANCE AND
CONTINUITY BETWEEN TERMINALS

1. Turn the ignition switch to "LOCK" (OFF) position.
2. Disconnect the engine-ECU <M/T> or

engine-A/T-ECU <A/T> connector.

3. Measure the resistance and check for continuity

between the terminals of the engine-ECU <M/T>
or engine-A/T-ECU <A/T> harness-side connector
while referring to the check chart.

NOTE:

.

1. When measuring resistance and checking

continuity, a harness for checking contact pin
pressure should be used instead of inserting a
test probe.

2. Checking need not be carried out in the order

given in the chart.

CAUTION

If the terminals that should be checked are
mistaken, or if connector terminals are not
correctly shorted to earth, damage may be
caused to the vehicle wiring, sensors,
engine-ECU <M/T> or engine-A/T-ECU <A/T>
and/or ohmmeter. Be careful to prevent this!
4. If the ohmmeter shows any deviation from the

standard value, check the corresponding sensor,
actuator and related electrical wiring, and the
repair or replace.

5. After repair or replacement, recheck with the

ohmmeter to confirm that the repair or
replacement has corrected the problem.

132

Power supply
voltage applied to
throttle valve control
servo

Ignition switch: ON

System voltage

133

Throttle valve control
servo (+)

• Ignition switch: ON

• Accelerator pedal: fully opened → fully

closed

Decreases slightly
(approximately 2 V) from
battery voltage.

141

Throttle valve control
servo (

−)

• Ignition switch: ON

• Accelerator pedal: fully closed → fully

opened

Decreases slightly
(approximately 2 V) from
battery voltage.

Terminal
No.

Check item

Check condition (Engine condition)

Normal condition

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-377

Engine-ECU <M/T> or engine-A/T-ECU <A/T> Harness Side Connector Terminal
Arrangement

1

2

3

4

5

6

7

8

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

24

25

26

27

36

37

38

39

40

31

32

33

34

35

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

67

68

69

70

61

62

63

64

65

66

71

72

73

74

75

76

77

78

79

80

81

82

83

84

85

86

87

88

89

91

92

93

94

95

96

97

98

99

101

100

103

102

104

105

106

107

108

109

110

111

112

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

113

114

115

116

117

118

119

120

AK303310

Engine-ECU <M/T> or Engine-A/T-ECU <A/T> Harness Side Connector

C-110

C-113

C-114

C-112

C-111

AC

Terminal
No.

Inspection item

Normal condition (Check condition)

1

− 34

No. 1 injector

10.5

− 13.5 Ω (at 20°C)

5

− 34

No. 2 injector

14

− 34

No. 3 injector

21

− 34

No. 4 injector

3

− 34

EGR valve (A)

20

− 24 Ω (at 20°C)

12

− 34

EGR valve (B)

19

− 34

EGR valve (C)

26

− 34

EGR valve (D)

10

− 34

Cylinder 2,3 oxygen sensor heater
(front)

4.5

− 8.0 Ω (at 20°C)

25

− 34

Cylinder 1,4 oxygen sensor heater
(front)

18

− 34

Cylinder 2,3 oxygen sensor heater
(rear)

11

− 18 Ω (at 20°C)

24

− 34

Cylinder 1,4 oxygen sensor heater
(rear)

23

− 34

Purge control solenoid valve

30

− 34 Ω (at 20°C)

33

− Body

earth

ECU earth

Continuity (2

Ω or less)

42

− Body

earth
144

−

Body
earth
145

−

Body
earth
34

− 95

Oil control valve

6.9

− 7.9 Ω (at 20°C)

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-378

INSPECTION PROCEDURE USING
OSCILLOSCOPE

M1131154500907

The output signals of the sensors and the conditions
of the actuation signals of the actuators can be
inspected visually by observing the waveforms on
the oscilloscope.

CAMSHAFT POSITION SENSOR AND
CRANK ANGLE SENSOR
Measurement Method

1. Disconnect the camshaft position sensor

connector and connect the special tool Test
harness (MB991709) in between (All terminals
should be connected).

2. Connect the oscilloscope special pattern pickup to

camshaft position sensor terminal No. 2.

3. Disconnect the crank angle sensor intermediate

connector and connect the special tool Test
harness (MB991658) in between.

4. Connect the oscilloscope special patterns pickup

to crank angle sensor terminal No. 2.

Alternate Method (Test harness not
available)

1. Connect the oscilloscope special patterns pickup

to engine-ECU <M/T> or engine-A/T-ECU <A/T>
terminal No. 71 (When checking the camshaft
position sensor signal wave pattern).

2. Connect the oscilloscope special patterns pickup

to engine-ECU <M/T> or engine-A/T-ECU <A/T>
terminal No. 70 (When checking the crank angle
sensor signal wave pattern).

Standard Wave Pattern

Observation condition

96

− 98

Engine coolant temperature sensor

14

− 17 kΩ (When coolant temperature is −20°C)

5.1

− 6.5 kΩ (When coolant temperature is 0°C)

2.1

− 2.7 kΩ (When coolant temperature is 20°C)

0.9

− 1.3 kΩ (When coolant temperature is 40°C)

0.48

− 0.68 kΩ (When coolant temperature is 60°C)

0.26

− 0.36 kΩ (When coolant temperature is 80°C)

96

− 99

Intake air temperature sensor

13

− 17 kΩ (When intake air temperature is −20°C)

5.3

− 6.7 kΩ (When intake air temperature is 0°C)

2.3

− 3.0 kΩ (When intake air temperature is 20°C)

1.0

− 1.5 kΩ (When intake air temperature is 40°C)

0.56

− 0.76 kΩ (When intake air temperature is 60°C)

0.30

− 0.45 kΩ (When intake air temperature is 80°C)

133

− 141 Throttle actuator control motor

0.3

− 100 Ω (at 20°C)

Terminal
No.

Inspection item

Normal condition (Check condition)

1 2 3

3

2

1

AK304513

Special patterns
pick-up

Oscilloscope

AC

Camshaft position
sensor connector

Crank angle sensor
intermediate
connector

Function

Special patterns

Pattern height

Low

Pattern selector

Display

Engine speed

Idle