Mazda 6. Manual - part 86

CONTROL SYSTEM 

U–17

U

Defroster Control

1. When the airflow mode selector dial is turned to DEFROSTER position, a wire moves the airflow mode main 

link, turning the airflow mode to DEFROSTER.

2. The defroster switch turns on at the same time, and the CPU sends a signal to turn the air intake mode to 

FRESH.

3. The air intake actuator operates and turns the air intake mode to FRESH.

.

X: Operates

–: Does not operate

A6E8540T034

1

Climate control unit

2

Airflow mode selector dial

3

DEFROSTER

4

Wire

5

Move

6

Airflow mode main link

7

Defroster switch

8

FRESH signal

9

Air intake actuator

10

FRESH

Airflow mode

Air intake mode (REC/FRESH switch 

pushed)

Defroster control

VENT

REC 

⇔

 FRESH

–

BI-LEVEL

REC 

⇔

 FRESH

–

HEAT

REC 

⇔

 FRESH

–

HEAT/DEF

REC 

⇔

 FRESH

–

DEFROSTER

FRESH

x

U–18

CONTROL SYSTEM 

A/C Compressor Control

•

The center panel sends an A/C signal to the PCM via the refrigerant pressure switch based on signals sent 
from the A/C switch, fan switch and evaporator temperature sensor.

•

The PCM controls the A/C relay and IAC valve based on the input signal from the center panel.

.

A/C signal on/off control

•

The center panel turns the A/C signal (magnetic clutch) on and off based on the temperature of the air passing 
through the evaporator when the A/C and fan switches are on. This keeps the evaporator surface temperature 
within the specified range, preventing the evaporator from freezing while the fan switch and A/C switch are 
turned on.

.

End Of Sie

A6E8540T049

1

Evaporator temperature sensor

2

A/C signal

3

Center panel

4

Output

5

A/C  relay

6

Magnetic clutch

7

IAC  valve

A6E8540T047

1

A/C signal on/off decision

2

Evaporator temperature sensor

3

A/C signal

CONTROL SYSTEM 

U–19

U

FULL-AUTO AIR CONDITIONER CONTROL SYSTEM

A6E854001044T01

Block Diagram

•

The control system consists of input components (sensors), output components (actuators, magnetic clutch, 
power MOS FET, and other parts), and a control device (climate control unit).

.

A6E8540T050

1

Ambient temperature sensor

2

Cabin temperature sensor

3

Water temperature sensor

4

Evaporator temperature sensor

5

Solar radiation sensor

6

Climate control unit

7

Airflow temperature control

8

Airflow volume control

9

Airflow mode control

10

Air intake control

11

A/C compressor control

12

Air mix actuator

13

Power MOS FET

14

Blower motor

15

Airflow mode actuator

16

Air intake actuator

17

Refrigerant pressure switch (HI and LO pressure)

18

Refrigerant pressure switch (middle pressure) (L3 
engine only)

19

A/C cut control

20

Idle speed control

21

A/C relay

22

Thermal protector

23

Magnetic clutch

24

IAC valve

U–20

CONTROL SYSTEM 

System Wiring Diagram

.

A6E8540T040

1

Ambient temperature sensor

2

Cabin temperature sensor

3

Evaporator temperature sensor

4

Water temperature sensor

5

Solar radiation sensor

6

From  TNS  relay

7

Panel light control

8

Climate control unit

9

Each switch

10

Refrigerant pressure switch

11

Airflow mode actuator

12

Air mix actuator

13

Air intake actuator

14

From blower relay

15

Blower motor

16

Power MOS FET

17

From rear window defroster relay