Mitsubishi Grandis. Manual — part 758

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-283

SYMPTOM PROCEDURES

Inspection Procedure 1: Communication with Engine-ECU <M/T> or Engine-A/T-ECU <A/T> is Not
Possible.

OPERATION

• There is data communication between diagnosis

connector output terminal (terminal No. 7) and
engine-ECU <M/T> (terminal No. 74).

20

Overheating

P.13A-316

21

Abnormal rotation of fan motor

P.13A-318

22

Engine-ECU <M/T> or engine-A/T-ECU <A/T> power supply, engine control
relay, ignition switch-IG1 system

P.13A-321

23

Fuel pump system

P.13A-328

24

Fan control relay system

P.13A-340

25

A/C compressor relay system

P.13A-347

26

Ignition circuit system

P.13A-355

Inspection
procedure
No.

Trouble symptom

Reference
page

AK305574

1 2 3 4 5 6

12

11

10

1516

14

13

9

7 8

61
656667686970 717273
74757677787980 8182
8384

858687

8889

62

6364

C-126

MU803797

15

74

7

C-17

Diagnosis connector circuit

AB

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

C-112

(MU803804)

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

Diagnosis connector

O-L

O-L

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-284

COMMENT ON TROUBLE SYMPTOM

• The failure possibly occurs when engine-ECU

<M/T> or engine-A/T-ECU <A/T> detects
malfunction, or is caused by malfunction of open
or short in the combination meter circuit.

PROBABLE CAUSE

• Open/short circuit in engine-ECU <M/T> or

engine-A/T-ECU <A/T> power circuit

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

<A/T> and diagnosis connector for short circuit

• Failed engine-ECU <M/T>

• Failed engine-A/T-ECU <A/T>

DIAGNOSIS PROCEDURE

STEP 1: Check start - up.

Q: Is engine started

YES :

Go to Step 2 .

NO :

Check engine-ECU <M/T> or
engine-A/T-ECU <A/T> power supply,
engine control relay and ignition switch IG1
system (Refer to Inspection Procedure 22

P.13A-321

).

STEP 2: Connector check: C-112 engine-ECU
<M/T> connector or engine-A/T-ECU <A/T>
connector

Q: Is the check result normal?

YES :

Go to Step 3 .

NO :

Repair or replace.

STEP 3: Check harness between C-126 (terminal
No. 7) diagnosis connector and C-112 (terminal
No. 74) engine-ECU <M/T> connector or
engine-A/T-ECU <A/T> connector.

NOTE: Before checking harness, check intermediate
connectors C-17 and repair if necessary.

• Check communication line for open/short circuit

and damage.

Q: Is the check result normal?

YES :

Go to Step 4 .

NO :

Repair.

STEP 4: Check the trouble symptom.

Q: Does trouble symptom persist?

AK305617

Connector: C-112

C-112 (GR)

C-112 (GR)

AB

Harness side connector

<R.H. drive vehicles>

<L.H. drive vehicles>

AK305628

1 2 3 4 5 6

12

11

10

1516

14

13

9

7 8

AB

Harness side connector

Connector: C-126

C-126 (B)

AK305617

Connector: C-112

C-112 (GR)

C-112 (GR)

AB

Harness side connector

<R.H. drive vehicles>

<L.H. drive vehicles>

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-285

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 2: The Engine Warning Lamp Does Not Illuminate Right after the Ignition Switch
is Turned the "ON" Position

COMMENTS ON TROUBLE SYMPTOM

• The combination meter illuminates engine

warning lamp for 5 seconds just after the ignition
switch is in "ON" position.

• If engine warning lamp does not illuminate just

after the ignition switch is in "ON" position, the
failure is possibly caused by malfunction of
engine warning lamp, open or short in the
combination meter circuits and so on.

PROBABLE CAUSE

• Failed engine warming lamp

• Open/short circuit in combination meter

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 the trouble symptoms.

Q: Does trouble system persist?

YES :

Replace combination meter assembly.

NO :

Intermittent malfunction (Refer to GROUP
00

− How to Use

Troubleshooting/Inspection Service Points

P.00-5

).

Inspection Procedure 3: The Engine Warning Lamp Remains Illuminating and Never Goes Out

COMMENT ON TROUBLE SYMPTOM

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

has detected failed sensor or failed actuator. Or
failure is possibly caused by short circuit or other
faults.

PROBABLE CAUSE

• Short circuit in combination meter

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 the trouble symptoms.

Q: Does trouble symptom persist?

YES :

Replace combination meter assembly.

NO :

Intermittent malfunction (Refer to
GROUP00

− How to Use

Troubleshooting/Inspection Service Points

P.00-5

).

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-286

Inspection Procedure 4: Starting Impossible (No Initial Combustion) <M/T>

COMMENT ON TROUBLE SYMPTOM

• Failure is possibly caused by failed starter itself

or failed related circuit.

PROBABLE CAUSE

• Failed battery

• Failed starter motor

• Open/short circuit in starter associated circuit or

loose connector contact

AK305575

1

1 2 3

4 5 6

31

35363738394041 42 43
444546474849

50 51

5253

545556

57 58

32

33 34

1

M

Battery

OFF

ON

AB

Starter

B-115

B-116

(MU801211)

C-111

(MU803083)

B-17

B-W

C-307

2

7

B-W

Engine-ECU

B-Y

B-L

1

51

1

B-Y

C-18

IG2

ST

LOCK

ACC

IG1

Ignition switch

5

Stating impossible (no initial combustion) <M/T>

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