Mazda CX-9 Grand Touring. Manual - part 431

Temperature control 
dial (driver side): 
Set temperature at 
MAX HOT

1.0

mix actuator  



Front climate control 
unit: terminal voltage 
(2B)  

2G

Potentiometer 
input

Passenger-side 
front air mix 
actuator

Temperature control 
dial (passenger 
side): Set 
temperature at 
MAX COLD

1.0



Wiring harness: 
continuity, short circuit 
(Front climate control 
unit-passenger-side 
front air mix actuator: 
2G-E)  



Passenger-side front 
air mix actuator  



Front climate control 
unit: terminal voltage 
(2B)  

Temperature control 
dial (passenger 
side): Set 
temperature at 
MAX HOT

4.0

2H

Front 
evaporator 
temperature 
sensor input

Front evaporator 
temperature sensor

Compared with 
temperature 
detected by front 
evaporator 
temperature sensor

Refer to



Wiring harness: 
continuity (Front 
climate control unit--
front evaporator 
temperature sensor: 
2H-B, 2P-A)  



Wiring harness: short 
circuit (Front climate 
control unit-front 
evaporator temperature 
sensor: 2H-B)  



Front evaporator 
temperature sensor  

21

Ambient 
temperature 
sensor input

Ambient 
temperature sensor

Compared with 
temperature 
detected by ambient 
temperature sensor

Refer to



Wiring harness: 
continuity (Front 
climate control unit-
ambient temperature 
sensor: 21-B, 2P-A)  



Wiring harness: short 
circuit (Front climate 
control unit-ambient 
temperature sensor: 
21-B)  



Ambient temperature 
sensor  



Wiring harness: 
continuity (Front 
climate control unit-
rear evaporator 

 

2008 Mazda CX-9 Grand Touring 

2008 HVAC Control System (HVAC) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:12:36 AM

Page 42 

© 2005 Mitchell Repair Information Company, LLC. 

2J

Rear 
evaporator 
temperature 
sensor input

Rear evaporator 
temperature sensor

Compared with 
temperature 
detected by rear 
evaporator 
temperature sensor

Refer to

temperature sensor: 2J-
B, 2P-A)  



Wiring harness: short 
circuit (Front climate 
control unit-rear 
evaporator temperature 
sensor: 2J-B)  



Rear evaporator 
temperature sensor  

2K

Cabin 
temperature 
sensor input

Cabin temperature 
sensor

Compared with 
temperature 
detected by cabin 
temperature sensor

Refer to



Wiring harness: 
continuity (Front 
climate control unit-
cabin temperature 
sensor: 2K-B, 2P-A)  



Wiring harness: short 
circuit (Front climate 
control unit-cabin 
temperature sensor: 
2K-B)  



Cabin temperature 
sensor  

2L

-

-

-

-

-

2M

Solar radiation 
sensor(LH) 
input

Solar radiation 
sensor

Natural sunlight 
shined directly on 
the solar radiation 
sensor

4.0



Wiring harness: 
continuity (Front 
climate control unit-
solar radiation sensor: 
2M-C, 2B-A)  



Front climate control 
unit: terminal voltage 
(2B)  



Solar radiation sensor  

Blocking light to 
solar radiation 
sensor

1.0 or 
less

2N

Potentiometer 
input

Rear air mix 
actuator

Temperature control 
dial (rear side): Set 
temperature at 
MAX COLD

1.3



Wiring harness: 
continuity, short circuit 
(Front climate control 
unit-rear air mix 
actuator: 2N-E)  



Rear air mix actuator  



Front climate control 
unit: terminal voltage 
(2B)  

Temperature control 
dial (rear side): Set 
temperature at 
MAX HOT

4.0

Natural sunlight 
shined directly on 
the solar radiation 

4.0



Wiring harness: 
continuity (Front 
climate control unit-

 

2008 Mazda CX-9 Grand Touring 

2008 HVAC Control System (HVAC) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:12:36 AM

Page 43 

© 2005 Mitchell Repair Information Company, LLC. 

2O

Solar radiation 
sensor (RH) 
input

Solar radiation 
sensor

sensor

solar radiation sensor: 
20-B, 2B-A)  



Front climate control 
unit: terminal voltage 
(2B)  



Solar radiation sensor  

Blocking light to 
solar radiation 
sensor

1.0 or 
less

2P

Sensor ground



Driver-side 
front air mix 
actuator  



Passenger-
side front air 
mix actuator 



Front 
airflow 
mode 
actuator  



Ambient 
temperature 
sensor  



Cabin 
temperature 
sensor  



Front 
evaporator 
temperature 
sensor  



Rear air mix 
actuator  



Rear airflow 
mode 
actuator  



Rear 
evaporator 
temperature 
sensor  

Under any 
condition: Inspect 
for continuity to 
ground

1.0 or 

less



Front climate control 
unit: terminal voltage 
(1X)  

3A

-

-

-

-

-

3B

-

-

-

-

-

Rear climate 

Rear climate 

Rear control switch 
on

B+



Wiring harness: 
continuity (Front 
climate control unit-
rear climate control 
unit: 3C-F)  



Wiring harness: short 

 

2008 Mazda CX-9 Grand Touring 

2008 HVAC Control System (HVAC) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:12:36 AM

Page 44 

© 2005 Mitchell Repair Information Company, LLC. 

3C

control unit 
display

control unit

Rear control switch 
off

1.0 or 
less

circuit (Front climate 
control unit-rear 
climate control unit: 
3C-F)  



Front climate control 
unit: terminal voltage 
(1W, 1X)  

3D

TNS signal

TNS relay

Turn the headlight 
switch to the off 
position

1.0 or 

less



Wiring harness: short 
circuit (Front climate 
control unit-TNS relay 
(main fuse block): 3D-
D)  



ILLUMI 10 A fuse  



TNS relay  



Headlight switch  

Turn the headlight 
switch to the TNS 
position

B+



Wiring harness: 
continuity, short circuit 
(Front climate control 
unit-TNS relay (main 
fuse block): 3D-D)  



ILLUMI 10 A fuse  



TNS relay  



Headlight switch  

3E

Rear fan 
control volume

Rear climate 
control unit

Airflow 
volume 
control dial

Off

1.0 or 

less



Front climate control 
unit: terminal voltage 
(1T)  



Wiring harness: 
continuity, short circuit 
(Front climate control 
unit-rear climate 
control unit: 3E-A)  



Rear climate control 
unit  

1st.

Approx. 
1.3

Max 
HI

Approx. 

4.0

3F

TNS signal

Rear climate 
control unit

Turn the headlight 
switch to the off 
position

1.0 or 

less



Wiring harness: 
continuity, short circuit 
(Front climate control 
unit-rear climate 
control unit: 3F-H)  



TNS relay  



Headlight switch  

Turn the headlight 
switch to the TNS 
position

B+

Temperature control 
dial (rear side): 

1.0 or 



Wiring harness: 

 

2008 Mazda CX-9 Grand Touring 

2008 HVAC Control System (HVAC) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:12:36 AM

Page 45 

© 2005 Mitchell Repair Information Company, LLC.