Mitsubishi Grandis. Manual - part 755

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-271

YES : 

Go to Step 5 .

NO : 

Repair.

STEP 9. Connector check: C-113 engine-ECU 
<M/T> connector or engine-A/T-ECU <A/T> 
connector

Q: Is the check result normal?

YES : 

Go to Step 10 .

NO : 

Repair or replace.

STEP 10. Check harness between C-102 (terminal 
No. 1) accelerator pedal position sensor 
connector and C-113 (terminal No. 92) 
engine-ECU <M/T> connector or engine-A/T-ECU 
<A/T> connector.

• Check power supply line for damage.

Q: Is the check result normal?

YES : 

Go to Step 11 .

NO : 

Repair.

AK305616AB

Connector: C-113

<L.H. drive vehicles>

<R.H. drive vehicles>

C-113 (GR)

C-113 (GR)

91

92

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120

Harness side connector

AK305627

1

6 5 4 3 2

Connector: C-102

AB

C-102 (B)

Harness side
connector

C-102 (B)

<L.H. drive vehicles>

<R.H. drive vehicles>

AK305616AB

Connector: C-113

<L.H. drive vehicles>

<R.H. drive vehicles>

C-113 (GR)

C-113 (GR)

91

92

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Harness side connector

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-272

STEP 11. Check harness between C-102 (terminal 
No. 4) accelerator pedal position sensor 
connector and C-113 (terminal No. 97) 
engine-ECU <M/T> connector or engine-A/T-ECU 
<A/T> connector.

• Check power supply line for damage.

Q: Is the check result normal?

YES : 

Go to Step 12 .

NO : 

Repair.

STEP 12. Check harness between C-102 (terminal 
No. 3) accelerator pedal position sensor 
connector and C-113 (terminal No. 114) 
engine-ECU <M/T> connector or engine-A/T-ECU 
<A/T> connector.

• Check output line for damage.

Q: Is the check result normal?

YES : 

Go to Step 13.

NO : 

Repair.

AK305627

1

6 5 4 3 2

Connector: C-102

AB

C-102 (B)

Harness side
connector

C-102 (B)

<L.H. drive vehicles>

<R.H. drive vehicles>

AK305616AB

Connector: C-113

<L.H. drive vehicles>

<R.H. drive vehicles>

C-113 (GR)

C-113 (GR)

91

92

93

94

95

96

97

98

99

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

Harness side connector

AK305627

1

6 5 4 3 2

Connector: C-102

AB

C-102 (B)

Harness side
connector

C-102 (B)

<L.H. drive vehicles>

<R.H. drive vehicles>

AK305616AB

Connector: C-113

<L.H. drive vehicles>

<R.H. drive vehicles>

C-113 (GR)

C-113 (GR)

91

92

93

94

95

96

97

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100

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102

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104

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109

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113

114

115

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119

120

Harness side connector

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-273

STEP 13. Check harness between C-102 (terminal 
No. 6) accelerator pedal position sensor 
connector and C-113 (terminal No. 107) 
engine-ECU <M/T> connector or engine-A/T-ECU 
<A/T> connector.

• Check output line for damage.

Q: Is the check result normal?

YES : 

Go to Step 14 .

NO : 

Repair.

STEP 14. Replace the accelerator pedal assembly

• After replacing the accelerator pedal assembly, 

re-check the trouble symptoms.

Q: Is the check result normal?

YES : 

Check end.

NO : 

Replace  engine-ECU <M/T> or 
engine-A/T-ECU <A/T>.

AK305627

1

6 5 4 3 2

Connector: C-102

AB

C-102 (B)

Harness side
connector

C-102 (B)

<L.H. drive vehicles>

<R.H. drive vehicles>

AK305616AB

Connector: C-113

<L.H. drive vehicles>

<R.H. drive vehicles>

C-113 (GR)

C-113 (GR)

91

92

93

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95

96

97

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Harness side connector

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-274

Code No. P2173: Abnormal Intake Air Amount

FUNCTION

• Engine-ECU <M/T> or engine-A/T-ECU <A/T> 

decides the allowable intake air amount in 
accordance with the engine speed and the target 
opening angle of throttle valve.

• Engine-ECU <M/T> or engine-A/T-ECU <A/T> 

checks whether the actual intake air amount is 
more than the allowable intake air amount.

TROUBLE JUDGMENT

Check Condition

• While engine is running.

Judgment Criterion

• The actual intake air amount is more than the 

allowable in take air amount for 1.5 seconds.

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

• Failed air flow sensor.

• Throttle valve faulty operation.

• Failed throttle position sensor

• Failed engine-ECU <M/T>

• Failed engine-A/T-ECU <A/T>

DIAGNOSIS

STEP 1. MUT-III diagnosis code

Q: Diagnosis code set?

YES : 

Inspection chart for diagnosis code (Refer 

to 

P.13A-20

).

NO : 

Go to Step 2 .

STEP 2. Replace the air flow sensor.

• After replacing the air flow sensor, re-check the 

trouble symptoms.

Q: Is the check result normal?

YES : 

Go to Step 3 .

NO : 

Check end.

STEP 3. Replace the throttle body assembly.

• After replacing the throttle body assembly, 

re-check the trouble symptoms.

Q: Is the check result normal?

YES : 

Replacing engine-ECU <M/T> or 

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

NO : 

Check end.

Code No. U1073: Bus Off

CAUTION

If diagnosis code U1073 is output from 
engine-ECU <M/T> or engine-A/T-ECU <A/T> 
surely perform CAN busline diagnosis.

CAUTION

Replace ECU after certainly confirming that the 
communication circuits are normal.

TROUBLE JUDGMENT

Check Condition

• All the time

Judgment Criterion

• When the buss off error is detected.

COMMENT ON TROUBLE SYMPTOM

• The failure is possibly caused by malfunction of 

the harness and connector in CAN busline or by 
malfunction in engine-ECU <M/T> or 
engine-A/T-ECU <A/T>.

PROBABLE CAUSE

• Failed engine-ECU <M/T>

• Failed engine-A/T-ECU <A/T>

DIAGNOSIS

STEP 1. MUT-III CAN bus diagnostics

• Using MUT-III, perform CAN busline diagnosis.

Q: Is the check result normal?

YES : 

 Go to Step 2 .

NO : 

Correct CAN busline (Refer to 54D 

− 

Diagnosis 

− Can Bus Diagnostics Chart 

P.54D-16

), and then go to Step 3 .