Mitsubishi Grandis. Manual — part 766

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-315

STEP 5. Connector check: C-111 engine-ECU
<M/T> connector or engine-A/T-ECU <A/T>
connector

Q: Is the check result normal?

YES :

Go to Step 6 .

NO :

Repair or replace.

STEP 6. Perform voltage measurement at C-111
engine-ECU <M/T> connector or engine-A/T-ECU
<A/T> connector

• Disconnect connector, and measure at harness

side.

• Ignition switch: ON

• Voltage between terminal No. 45 and earth.

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 8 .

NO :

Go to Step 7 .

AK305625AB

Connector: C-111

<L.H. drive vehicles>

<R.H. drive vehicles>

C-111 (GR)

C-111 (GR)

Harness side connector

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AK305625AB

Connector: C-111

<L.H. drive vehicles>

<R.H. drive vehicles>

C-111 (GR)

C-111 (GR)

Harness side connector

31

32

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TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-316

STEP 7. Check harness between C-111 (terminal
No. 45) engine-ECU <M/T> or engine-A/T-ECU
<A/T> and B-119 (terminal No. 1) alternator
connector.

• Check output line for open/short circuit.

Q: Is the check result normal?

YES :

replace alternator.

NO :

Repair.

STEP 8. Perform voltage measurement at C-111
engine-ECU <M/T> connector or engine-A/T-ECU
<A/T> connector.

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

<A/T> terminal voltage.

• Engine: Idling after warm-up

• Transmission: Neutral <M/T> or P range <A/T>

• Radiator fan: Inactive

• Voltage between terminal No. 45 and earth.

OK: Switching the headlamps to ON from
OFF causes the voltage to increase.

Q: Is the check result normal?

YES :

Go to Step 9 .

NO :

Replace alternator.

STEP 9. Check the trouble symptoms.

Q: Does trouble symptom persist?

YES :

Replace engine-ECU <M/T> or

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

NO :

Intermittent malfunction (Refer to GROUP
00

− How to Use

Troubleshooting/Inspection Service Points

P.00-5

).

Inspection Procedure 20: Overheating

COMMENT ON TROUBLE SYMPTOM

• Failure is possibly caused by failed engine

cooling system, failed fan controller, failed engine

coolant temperature sensor or other faults.

AK305625AB

Connector: C-111

<L.H. drive vehicles>

<R.H. drive vehicles>

C-111 (GR)

C-111 (GR)

Harness side connector

31

32

33

34

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AK300990

2

1

3

4

AC

B-119 (GR)

Connector: B-119

Harness side connector

AK305625AB

Connector: C-111

<L.H. drive vehicles>

<R.H. drive vehicles>

C-111 (GR)

C-111 (GR)

Harness side connector

31

32

33

34

35

36

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TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-317

PROBABLE CAUSE

• Insufficient or deteriorated engine coolant

• Failed fan controller

• Failed engine coolant temperature sensor

• Failed thermostat

• Failed water pump

• Failed radiator core

• Failed engine-ECU <M/T>

• Failed engine-A/T-ECU <A/T>

DIAGNOSIS PROCEDURE

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. Check engine coolant
NOTE: If engine coolant level falls too early, check
for leaky spots, and repair if necessary.

• Check engine coolant (Refer to GROUP 14 −

On-vehicle Service

− Engine Coolant Leak Check

P.14-16

).

Q: Is the check result normal?

YES :

Go to Step 3 .

NO :

Replace or add engine coolant.

STEP 3. MUT-III actuator test

• Item 21: Fan controller

OK: Fan motor rotating

Q: Is the check result normal?

YES :

Go to Step 4 .

NO :

Check fan control relay system (Refer to
Inspection Procedure 24

P.13A-340

).

STEP 4. MUT-III data list

• Item 21: Engine coolant temperature sensor

OK:

Engine cold state: At ambient temperature

(atmospheric temperature) or equivalent.

Engine hot state: At 80

− 120°C

Q: Is the check result normal?

YES :

Go to Step 5 .

NO :

Check engine coolant temperature sensor
system (Refer to Code No. P0115

P.13A-37

).

STEP 5. Check thermostat.

• Check thermostat (Refer to GROUP 14 −

Thermostat

− Thermostat Inspection

P.14-21

).

Q: Is the check result normal?

YES :

Go to Step 6 .

NO :

Replace thermostat.

STEP 6. Check water pump.

• Check water pump.

Q: Is the check result normal?

YES :

Replace radiator.

NO :

Replace water pump.

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-318

Inspection Procedure 21: Abnormal Rotation of Fan Motor

OPERATION

• The control (duty) signal is inputted to the fan

controller (terminal No. 2) from the engine-ECU
<M/T> or engine-A/T-ECU <A/T> (terminal No.
17).

FUNCTION

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

<A/T> inputs a duty signal suitable for the engine
coolant temperature, vehicle speed and A/C
switch position to the fan controller. In response
to the signal, the fan controller controls the
rotating speeds of the radiator fan and A/C
condenser fan (The fan speed becomes higher
as the average voltage of the terminal comes
nearer to 5V).

PROBABLE CAUSE

• Failed fan controller

• Open/short circuit in fan controller circuit or loose

connector contact

• Failed engine-ECU <M/T>

• Failed engine-A/T-ECU <A/T>

AK305577

1

2

3

5

6 7 8 9

4

20

21 22

232425

2627

10111213

14 15

16 1718

19

1 2 3

C-110

(MU803802)

AB

Fan controller

Fan
control
circuit

A-26
(MU802322)

2

L-W

L-W

8

A-16

17

Fan controller (Radiator fan, A/C condensor fan) circuit

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

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