Mitsubishi Grandis. Manual - part 698

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-43

STEP 14. 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 15 .

NO : 

Repair or replace.

STEP 15. Check harness between B-08 (terminal 
No. 1) engine coolant temperature sensor 
connector and C-113 (terminal No. 98) 
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 7 .

NO : 

Repair.

AK305616AB

Connector: C-113

<L.H. drive vehicles>

<R.H. drive vehicles>

C-113 (GR)

C-113 (GR)

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Harness side connector

AK300971

1

2

AC

Harness side connector

B-08 (B)

Connector: B-08

AK305616AB

Connector: C-113

<L.H. drive vehicles>

<R.H. drive vehicles>

C-113 (GR)

C-113 (GR)

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Harness side connector

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-44

Code No. P0122: Throttle Position Sensor (Main) Circuit Low Input

OPERATION

• A power voltage of 5 V is applied to the 

electronic-controlled throttle valve (terminal No. 
5) from the engine-ECU <M/T> or 
engine-A/T-ECU <A/T> (terminal No. 106).

• The power voltage is earthed to the engine-ECU 

<M/T> or engine-A/T-ECU <A/T> (terminal No. 
105) from the electronic-controlled throttle valve 
(terminal No. 3).

• The sensor signal is inputted to the engine-ECU 

<M/T> or engine-A/T-ECU <A/T> (terminal No. 
115) from the electronic-controlled throttle valve 
output terminal (terminal No. 4).

FUNCTION

• The throttle position sensor converts the throttle 

valve position into voltage and inputs it into the 
engine-ECU <M/T> or engine-A/T-ECU <A/T>.

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

<A/T> controls the throttle valve position.

TROUBLE JUDGMENT

Check Condition

• Ignition switch is in "ON" position.

Judgment Criterion

• Throttle position sensor (main) output voltage is 

0.35 V or less for 0.5 second.

PROBABLE CAUSE

• Failed throttle position sensor (main)

AK305550

6

1 2 3 4 5

9192

939495

96979899

100

105

113114

115116117

118119120

106

107108109

110111112

101102103

104

AB

5 V

106

5

Electronic-controlled
throttle valve

B

B

G

R

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

115

105

4

3

Throttle position sensor (main) circuit

B-06

C-113

(MU803805)

Wire colour code
B: Black  LG: Light green  G: Green  L: Blue  W: White  Y: Yellow  SB: Sky blue  BR: Brown  O: Orange  GR: Gray
R: Red  P: Pink  V: Violet

(main)

Hall IC

C-115

7

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-45

• Open/short circuit in throttle position sensor 

circuit or loose connector contact

• Failed engine-ECU <M/T>

• Failed engine-A/T-ECU <A/T>

DIAGNOSIS PROCEDURE

STEP 1. MUT-III data list

• Refer to Data List Reference Table 

P.13A-363

.

a. Item 79: Throttle position sensor (main)

Q: Is the check result normal?

YES : 

Intermittent malfunction (Refer to GROUP 

00 

− How to Use 

Troubleshooting/Inspection Service Points 

P.00-5

).

NO : 

Go to Step 2 .

STEP 2. Connector check: B-06 
electronic-controlled throttle valve connector

Q: Is the check result normal?

YES : 

Go to Step 3 .

NO : 

Repair or replace.

STEP 3. Perform voltage measurement at B-06 
electronic-controlled throttle valve connector.

• Disconnect connector, and measure at harness 

side.

• Ignition switch: ON 

• Voltage between terminal No. 5 and earth.

OK: 4.9 

− 5.1 V

Q: Is the check result normal?

YES : 

Go to Step 7 .

NO : 

Go to Step 4 .

STEP 4. 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 5 .

NO : 

Repair or replace.

AK300972

1

6 5 4 3 2

AC

Harness side connector

Connectors: B-06

B-06 (B)

AK300972

1

6 5 4 3 2

AC

Harness side connector

Connectors: B-06

B-06 (B)

AK305616AB

Connector: C-113

<L.H. drive vehicles>

<R.H. drive vehicles>

C-113 (GR)

C-113 (GR)

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120

Harness side connector

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-46

STEP 5. Check harness between B-06 (terminal 
No. 5) electronic-controlled throttle valve 
connector and C-113 (terminal No. 106) 
engine-ECU <M/T> or engine-A/T-ECU <A/T> 
connector.

• Check power supply line for open/short circuit.

Q: Is the check result normal?

YES : 

Go to Step 6 .

NO : 

Repair.

STEP 6. MUT-III data list

• Refer to Data List Reference Table 

P.13A-363

.

a. Item 79: Throttle position sensor (main)

Q: Is the check result normal?

YES : 

Intermittent malfunction (Refer to GROUP 

00 

− How to Use 

Troubleshooting/Inspection Service Points 

P.00-5

).

NO : 

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

STEP 7. 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 8 .

NO : 

Repair or replace.

AK300972

1

6 5 4 3 2

AC

Harness side connector

Connectors: B-06

B-06 (B)

AK305616AB

Connector: C-113

<L.H. drive vehicles>

<R.H. drive vehicles>

C-113 (GR)

C-113 (GR)

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120

Harness side connector

AK305616AB

Connector: C-113

<L.H. drive vehicles>

<R.H. drive vehicles>

C-113 (GR)

C-113 (GR)

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92

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Harness side connector