Mitsubishi Outlander (2003+). Manual - part 123

SPECIAL TOOL

ENGINE COOLING

14-3

SPECIAL TOOL

M1141000600291

TROUBLESHOOTING

INSPECTION CHART FOR TROUBLE 
SYMPTOMS

M1141005600412

Tool

Number

Name

Use

MB991871

LLC changer

Coolant refilling

MB991223 

A: MB991219 
B: MB991220 
C: MB991221 
D: MB991222 

Harness set 

A: Test harness 
B: LED harness 
C: LED harness 

adapter

D: Probe

Making voltage and 
resistance measurement 
during troubleshooting

A: Connector pin contact 

pressure inspection

B: Power circuit inspection
C: Power circuit inspection
D: Commercial tester 

connection

MB991871

MB991223

A

B

C

D

AC

Trouble symptom

Inspection 
procedure No.

Reference page

Radiator fan and condenser fan do not operate

1

P.14-4

Radiator fan and condenser fan do not change speed or stop 

2

P.14-12

Radiator fan does not operate

3

P.14-15

Condenser fan does not operate

4

P.14-16

TROUBLESHOOTING

ENGINE COOLING

14-4

INSPECTION PROCEDURE FOR 
TROUBLE SYMPTOMS

INSPECTION PROCEDURE 1: Radiator Fan and Condenser Fan do not Operate

CIRCUIT OPERATION

•

The fan controller is powered from fusible link 
No.2.

•

The engine-ECU <M/T> or engine-A/T-ECU 
<A/T> uses input signals from the A/C switch, the 
water temperature sensor unit and the vehicle 
speed sensor <M/T> or the output shaft speed 
sensor <A/T> to control the speed of the radiator 
fan motor and the condenser fan motor.

•

The engine-ECU <M/T> or engine-A/T-ECU 
<A/T> controls the fan controller to activate the 
radiator fan motor and the condenser fan motor.

TECHNICAL DESCRIPTION

•

The cause could be a malfunction of the fan 
controller power supply or earth 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 

FUSIBLE 
LINK No.2

FAN CONTROL 
RELAY

RADIATOR
FAN MOTOR

CONDENSER
FAN MOTOR

FAN
CONTROLLER

ENGINE CONTROL 
RELAY

AC309494

ENGINE-ECU <M/T>OR
ENGINE-A/T-ECU <A/T>

NOTE

4G63
4G69

Radiator Fan and Condenser Fan Drive Circut

AB

TROUBLESHOOTING

ENGINE COOLING

14-5

•

If the communication line wiring harness between 
the fan controller and the engine-ECU <M/T> or 
engine-A/T-ECU <A/T> is short-circuited to earth, 
the radiator fan motor and the condenser fan 
motor will not rotate.

•

The cause could also be a malfunction of input 
signal from the A/C switch, the water temperature 
sensor unit and the vehicle speed sensor <M/T> 
or the output shaft speed sensor <A/T> to the 
engine-ECU <M/T> or engine-A/T-ECU <A/T>.

•

The cause could also be a malfunction of the fan 
controller or the engine-ECU <M/T> or 
engine-A/T-ECU <A/T>.

TROUBLESHOOTING HINTS

•

Malfunction of fusible link No.2

•

Malfunction of fan control relay

•

Malfunction of cooling fan motor

•

Malfunction of fan controller

•

Malfunction of engine-ECU <M/T> or 
engine-A/T-ECU <A/T>

•

Damaged wiring harness or connector

DIAGNOSIS

STEP 1. Check the radiator fan motor.

Refer to 

P.14-20

.

Q: Is the radiator fan motor in good condition?

YES : 

Go to Step 2.

NO : 

Replace the radiator fan motor (Refer to 

P.14-29

). Then go to Step 24.

STEP 2. Measure the power supply voltage at fan 
controller connector A-20.

(1) Disconnect fan controller connector A-20 and 

measure wiring harness side connector.

(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between fan controller 

connector A-20 terminal 3 and body earth.

•

The voltage should measure system voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) 

position.

(5) Connect fan controller connector A-20.

Q: Is the measured voltage system voltage?

YES : 

Go to Step 17.

NO : 

Go to Step 3.

STEP 3. Check the fan controller connector A-20.

Q: Is the connector in good condition?

YES : 

Go to Step 4.

NO : 

Repair or replace the connector. Then go to 
Step 24.

STEP 4. Check the fusible link No.2.

Q: Is the fusible link No.2 in good condition?

AC301902

3

2

1

A-20

Connector: A-20

AB

3

2

1

AC201418

Connector A-20

(Conponent side)

AF

AC301902

3

2

1

A-20

Connector: A-20

AB

AC309505 AB

Fusible link
No.2

Relay box

TROUBLESHOOTING

ENGINE COOLING

14-6

YES : 

Go to Step 5.

NO : 

Replace the fusible link No.2. Then go to 
Step 24.

STEP 5. Measure the power supply voltage at fan 
control relay connector A-10X.

(1) Disconnect fan control relay connector A-10X 

(remove the fan control relay) and measure relay 
box side connector.

(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between fan control relay 

connector A-10X terminal 4 and body earth.

•

The voltage should measure system voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) 

position.

(5) Connect fan control relay connector A-10X 

(install the fan control relay).

Q: Is the measured voltage system voltage?

YES : 

Go to Step 8.

NO : 

Go to Step 6.

STEP 6. Check the fan control relay connector 
A-10X.

Q: Is the connector in good condition?

YES : 

Go to Step 7.

NO : 

Repair the connector or replace the relay 
box. Then go to Step 24.

STEP 7. Check the harness wire between fusible 
link No.2 and fan control relay connector A-10X 
terminal 4.

Q: Is the harness wire in good condition?

YES : 

An intermittent malfunction is suspected 

(Refer to GROUP 00 - How to use 
troubleshooting 

P.00-6

).

NO : 

Repair the damaged harness wire. Then go 
to Step 24.

AC309505 AC

Fan control relay

Relay box

Connector: A-10X

A-10X

AC303511AD

A-10X Connector
(Relay box side)

AC309505 AC

Fan control relay

Relay box

Connector: A-10X

A-10X

AC309505 AB

Fusible link
No.2

Relay box

AC309505 AC

Fan control relay

Relay box

Connector: A-10X

A-10X