Mitsubishi Grandis. Manual - part 401

HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS

GENERAL

00-10

IF INSPECTING WITH THE CONNECTOR 
CONNECTED <WATERPROOF 
CONNECTORS>

CAUTION

Never insert a test probe from the harness side, 
as this will reduce the waterproof performance 
and result in corrosion.

Use the special tools such as test harness, harness 
connector or check harness.

IF INSPECTING WITH THE CONNECTOR 
CONNECTED <ORDINARY 
(NON-WATERPROOF) CONNECTORS>

Insert a test bar from the wiring harness side. If a test 
bar cannot be inserted due to a too small pin cell 
(e.g. control unit connector pins), use the probe 
(MB991222) of the special tool Harness Set 
(MB991223). Never attempt to insert the test bar into 
a too small pin cell forcibly.

IF INSPECTING WITH THE CONNECTOR 
DISCONNECTED <WHEN INSPECTING A 
FEMALE PIN>

CAUTION

• Use the special tool Check Harness 

(MB991219). If the test bar is inserted forcibly, 
it will cause a poor contact. 

• If the connector is disconnected, a diagnosis 

code may be stored for the system to be 
checked or other systems.

Use the Check Harness (MB991219) of the special 
tool Harness Set (MB991223).

IF INSPECTING WITH THE CONNECTOR 
DISCONNECTED <WHEN INSPECTING A 
MALE PIN>

CAUTION

• Be careful not to short the connector pins 

with the test bars. To do so may damage the 
circuits inside the ECU.

• If the connector is disconnected, a diagnosis 

code may be stored for the system to be 
checked or other systems.

Touch the pin directly with the test bar.

AC105597AB

Special tool

AC105598

MB991222

AB

AC105599

MB991219

AB

AC105600

HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS

GENERAL

00-11

CONNECTOR INSPECTION SERVICE 
POINTS
VISUAL INSPECTION

•

Connector is disconnected or improperly connected

• Connector pins are pulled out

• Due to harness tension at terminal section

• Low contact pressure between male and female 

terminals

• Low connection pressure due to rusted terminals 

or foreign matter lodged in terminals

CONNECTOR PIN INSPECTION

If the connector pin stopper is damaged, the terminal 
connections (male and female pins) will not be 
perfect even if the connector body is connected, and 
the pins may pull out of the reverse side of the 
connector. Therefore, gently pull the harnesses one 
by one to make sure that no pins pull out of the 
connector.

CONNECTOR ENGAGEMENT 
INSPECTION

Use special tool inspection harness (MB991219) 
(connector pin connection pressure inspection 
harness of the inspection harness set) to inspect the 
engagement of the male pins and females pins. (Pin 
drawing force: 1 N or more)

AC300896AB

Connector disconnected or
improperly connected

Stretched or broken wires

Low contact
pressure

Harness wire breakage
at terminal section

Good

Bad

AC300898

AC300899AB

MB991219

HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS

GENERAL

00-12

INSPECTION SERVICE POINTS FOR A 
BLOWN FUSE

CAUTION

A diagnosis code may be stored due to a blown 
fuse.

Remove the blown fuse and measure the resistance 
between the load side of the blown fuse and the 
earth. Close the switches of all circuits which are 
connected to this fuse. If the resistance is almost 0 

Ω 

at this time, there is a short somewhere between 
these switches and the load. If the resistance is not 0 
Ω, there is no short at the present time, but a 
momentary short has probably caused the fuse to 
blow.
The main causes of a short circuit are the following.

• Harness being clamped by the vehicle body

• Damage to the outer casing of the harness due to 

wear or heat

• Water getting into the connector or circuitry

• Human error (mistakenly shorting a circuit, etc.)

HOW TO COPE WITH INTERMITTENT 
MALFUNCTIONS

Intermittent malfunctions often occur under certain 
conditions, and if these conditions can be 
ascertained, determining the cause becomes simple. 
In order to ascertain the conditions under which an 
intermittent malfunction occurs, first ask the 
customer for details about the driving conditions, 
weather conditions, frequency of occurrence and 
trouble symptoms, and then try to recreate the 
trouble symptoms. Next, ascertain whether the 
reason why the trouble symptom occurred under 
these conditions is due to vibration, temperature or 
some other factor. If vibration is thought to be the 
cause, carry out the following checks with the 
connectors and components to confirm whether the 
trouble symptom occurs. The objects to be checked 
are connectors and components which are indicated 
by inspection procedures or given as probable 
causes (which generates diagnosis codes or trouble 
symptoms).

AC300900AB

Battery

Fuse

Load
switch

Load

Short-circuit
occurrence
section

AC300901

VEHICLE IDENTIFICATION

GENERAL

00-13

• Gently shake the connector up, down and to the 

left and right.

• Gently shake the wiring harness up, down and to 

the left and right.

• Gently rock each sensor and relay, etc. by hand.

• Gently shake the wiring harness at suspensions 

and other moving parts.

NOTE: If determining the cause is difficult, the drive 
recorder function of the MUT-III can also be used. 
(For details on how to use the MUT-III, refer to the 
"MUT-III operation manual).

HOW TO TREAT PAST TROUBLE

1. Establish from the customer whether a fuse or 

connector has been replaced or disconnected.

2. If yes, erase the diagnosis code, and then check 

that no diagnostic code is reset. If no diagnosis 
code is reset, the diagnosis is complete.

3. If no, follow the applicable Diagnostic Trouble 

Code Chart. Then check the wiring harness and 
connector, and refer to "How to Cope with 
Intermittent Malfunction ."

VEHICLE IDENTIFICATION

M1001000400768

VEHICLE IDENTIFICATION CODE PLATE

The vehicle information code plate is riveted to the 
back of the hood.

• The plate shows model code, engine model, 

transmission model and body colour code.

• For monotone colour vehicles, the body colour 

code shall be indicated.

MODELS

MODEL CODE

AC310096

Hood

AC

1

2

3

4

5

6

7

No. Item

Content

1

MODEL

NA4W

Vehicle model

LNHYL6

Model series

2

ENGINE

4G69

Engine model

3

EXT

W32A

Exterior code

4

TRANS 
AXLE

F5M42

Transmission model

5

COLOR

W32

Body colour code

6

INT

22T

Interior code

7

OPT

Z36

Equipment code

Model code

Engine model

Transmission model

Fuel supply 
system

NA4W

LNUYL6/R6

4G69-SOHC-MIVEC 
(2,378 mL)

F5M42 <2WD, 5M/T>

MPI

LRUYL6/R6

F4A4B <2WD, 4A/T with sport mode>

LNHYL6/R6

F5M42 <2WD, 5M/T>

LRHYL6/R6

F4A4B <2WD, 4A/T with sport mode>