2.18.2 Schematic
2.18.2.1 Schematic

12

01

29

FANLO

FANHI

MPR

EO35

EO35

EO35

62

67

66

Main Relay

Engine 

Control 

Module

Fan Low Speed Relay

Fan High Speed Relay

Fan Assembly

FE02-7901b

Engine

Engine Cooling System JL4G15-D

2-839

2.18.3 Diagnostic Information and Procedures
2.18.3.1 Cooling Fan Circuit Diagnosis

Diagnostic Tips:

–

If there is an overheating complaint, verify whether the it is because the engine coolant boiling or the engine coolant temperature
gage indicates the coolant overheating. If the engine is overheating, but the cooling fan is still running, check the engine cooling
system.

–

If the fuse EF29 in underhood fuse block fuses immediately after installation, check whether the circuit between the cooling fan
high or Low-Speed relay and cooling fan motor is to short to ground. If the engine control module has just controlled relay pull-
in, EF29 fuses, then the cooling fan motor may be faulty.

–

When the Air-Conditioning system is switched on, the engine control module controls the cooling fan run at low speed. When
the Air-Conditioning high pressure is 1,520 Pa (220.5 psi), the engine control module will switch cooling fan from low speed to
high speed. When the Air-Conditioning high pressure drops back to 1,450 kPa (210.3 psi), the cooling fan will return to low speed.

–

Use scan tool "Function Test" to drive high or low speed cooling fan relay pull-in to confirm whether the fan works properly to
quickly determine the fault.

Note

Before carry out this diagnostic procedure, make sure check whether fuse EF29 works properly, whether main relay
works properly. When using scan tool "action test", make sure the scan tool communicates with ECM properly.

Step 1

Verify the fault.

Next

Step 2

Confirm whether the low speed cooling fan is running.

(a)

Turn the ignition switch to "OFF" position.

(b)

Connect scan tool to the datalink connector.

(c)

Start the engine to normal working temperature.

(d)

Turn off A/C switch.

(e)

Select in sequence: Engine / Data List / Engine Coolant
Temperature.

(f)

When the engine coolant temperature gage displays 95°C
(203 ºF) Cooling fan should be running at low speed.

Is cooling fan running at Low speed?

No

Refer to 

2.18.3.3

 

Low Speed Cooling Fan

Inoperative

Yes

Step 3

Confirm whether the high speed cooling fan is running.

(a)

Turn off A/C switch.

(b)

When the engine coolant temperature gage displays 99°C
(210.2 ºF) When the cooling fan should be running at high
speed.

Is the cooling fan running at high speed?

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Engine Cooling System JL4G15-D

Engine

No

Refer to 

2.18.3.2

 

High Speed Cooling Fan

Inoperative

Yes

Step 4

Turn on the A/C switch and confirm whether the low speed cooling fan is running.

(a)

Turn the ignition switch to "OFF" position.

(b)

Connect scan tool to datalink connector.

(c)

Select in sequence: Engine / Data List / Engine Coolant
Temperature.

(d)

When the engine coolant temperature is below 90°C
(194 ºF), Start the engine, turn on the A/C switch, cooling fan
should be running low speed.

Is cooling fan running at Low speed?

No

A/C system malfunction, Refer
to

8.2.7

 

Diagnostic Information and

Procedures

Yes

Step 5

Intermittent Fault. Refer to 

2.2.7.3

 

Intermittent Fault Check

.

2.18.3.2 High Speed Cooling Fan Inoperative

Note

Before carry out this diagnostic procedure, please Refer to the2.18.3.1

 

Cooling Fan Circuit Diagnosisprogram, which

will help with quick diagnostic.

Step 1

Check high speed cooling fan power supply.

1

2

3

Cooling Fan Harness Connector CA16

FE02-7801b

(a)

Turn the ignition switch to "OFF" position.

(b)

Disconnect cooling fan wiring harness connector CA16.

(c)

Turn the ignition switch to "ON" position.

(d)

Connect scan tool to the datalink connector.

(e)

Select in sequence: Engine / Action Test / Fan 2.

(f)

Make High-Speed relay work.

(g)

Measure voltage between cooling fan wiring harness
connector CA16 terminal No.2 and a reliable ground.

Standard Voltage: 11-14 V

Is the voltage specified Value?

No

Go to step 4

Yes

Step 2

Check the cooling fan ground circuit.

Engine

Engine Cooling System JL4G15-D

2-841

1

2

3

Cooling Fan Harness Connector CA16

FE02-7802b

(a)

Turn the ignition switch to "OFF" position.

(b)

Disconnect cooling fan wiring harness connector CA16.

(c)

Measure resistance between cooling fan wiring harness
connector CA16 terminal No.3 and a reliable ground.

Standard Resistance: Less than 1 Ω

Is the resistance specified Value?

No

CA16 terminal No.3 has poor connection to
ground. inspect and repair faulty part.

Yes

Step 3

Replace cooling fan.

Step 4

Use scan tool "Action Test" to drive the fan 2. Does high speed relay work?

No

Go to step 8

Yes

Step 5

Check high speed relay A terminal No.87 power supply.

1413 12 1110

5

1

2

3

4

6

7

8

9

J

L

K

I

G

D

C

B

E

F

A

86

86

30

87

85

86

86

87

87

87

30

30

30

85

85

85

2

2

3

3

5

5

1

1

1

2

5 3

1

2

5 3

86

87

30

1

1

2

5
3

2

5
3

85

EF01

EF21

EF18

EF25

EF20

EF29

EF06

EF02

EF30

EF17

EF19

EF23

EF22

EF26

EF24

EF08

EF27

EF28

EF05

EF07

EF16

EF04

EF03

EF15

EF12

EF10

EF1

1

EF09

EF13

EF14

EF32

EF31

A

86

87

30

85

FE02-7803b

(a)

Turn the ignition switch to "OFF" position.

(b)

Remove the High-Speed cooling fan relay A.

(c)

Measure voltage between high speed cooling fan relay A
terminal No.87 and a reliable ground.

Standard Voltage: 11-14 V

Is the voltage specified Value?

No

Relay A terminal No.87 power supply circuit
malfunction. inspect and repair faulty parts.

Yes

Step 6

Check high speed cooling fan relay A and cooling fan harness connector CA16 wiring harnesses.

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Engine Cooling System JL4G15-D

Engine