Mazda CX-9 Grand Touring. Manual - part 430

COLD

1O

Motor 
operation

Air intake actuator

REC switch: 
Switched to 
RECIRCULATE

1.0 or 

less



Wiring harness: 
continuity, short circuit 
(Front climate control 
unit-air intake actuator: 
1M-A, 1O-C)  



Air intake actuator  

REC switch: 
Switched to FRESH

B+

1P

Front blower 
motor 
feedback

Front power MOS 
FET

Airflow 
volume 
control dial

Off

Approx. 

7.3

1. Wiring harness: 

continuity, short circuit 
(Front climate control 
unit-front power MOS 
FET: 1P C, 1R A)  

2. Wiring harness: 

continuity (Front 
power MOS FET-body 
ground: D-ground)  

3. Front power MOS FET 

4. Front blower motor  

5. Front blower relay  

6. HEATER 50 A fuse  

1st.

Approx. 
5.4

2nd.

Approx. 

4.6

3rd.

Approx. 

3.7

4th.

Approx. 

2.9

5th.

Approx. 

2.0

6th.

Approx. 

1.1

7th,

1.0 or 

less

1Q

Rear window 
defroster 
switch

Rear window 
defroster relay

Rear window 
defroster switch on

1.0 or 

less



Wiring harness: 
continuity, short circuit 
(Front climate control 
unit-rear window 
defroster relay (main 
fuse block): 1Q-A)  



Rear window defroster 
relay  

Rear window 
defroster switch off

B+



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

1R

Front blower 
fan speed 
control

Front power MOS 
FET

Airflow 
volume 
control dial

Off

1.0 or 

less



Front climate control 
unit: terminal voltage 
(1P)  

1st.

Approx. 
2.1

2nd.

Approx. 

2.2

3rd.

Approx. 

2.3

4th.

Approx. 

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:12:36 AM

Page 38 

© 2005 Mitchell Repair Information Company, LLC. 

2.4

5th.

Approx. 

2.5

6th.

Approx. 

2.7

7th.

Approx. 

10.7

1S

A/C

Refrigerant 
pressure switch

Fan switch on, A/C 
switch on

1.0 or 

less



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

Fan switch off

B+



Wiring harness: 
continuity, short circuit 
(Front climate control 
unit-refrigerant 
pressure switch: 1S-B) 
(Refrigerant pressure 
switch-PCM: C-1B)  



Refrigerant pressure 
switch  



PCM: terminal voltage 
(1B)  

1T

Rear blower 
motor 
feedback

Rear power MOS 
FET

Rear airflow 
volume 
control dial

Off

Approx. 

8.5

1. Wiring harness: 

continuity, short circuit 
(Front climate control 
unit-rear power MOS 
FET: 1T D, 1V C)  

2. Wiring harness: 

continuity (Rear power 
MOS FET-body 
ground: A-ground)  

3. Rear power MOS FET 

4. Rear blower motor  

5. Rear blower relay  

6. R.HEATER 40 A fuse 

1st.

Approx. 
6.1

2nd.

Approx. 

4.8

3rd.

Approx. 

3.6

4th.

Approx. 

1.9

5th.

1.0 or 

less

1U

On-board 
diagnostic 
signal

Check connector

Check connector is 
shorted.

1.0 or 

less



Wiring harness: 
continuity (Front 
climate control unit-
check connector: 1U-
A)  

Other

B+



Wiring harness: short 
circuit (Front climate 
control unit-check 
connector: 1U-A)  

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:12:36 AM

Page 39 

© 2005 Mitchell Repair Information Company, LLC. 



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

1V

Rear blower 
fan speed 
control

Rear power MOS 
FET

Rear airflow 
volume 
control dial

Off

1.0 or 

less



Front climate control 
unit: terminal voltage 
(1T)  

1st.

Approx. 
2.1

2nd.

Approx. 

2.2

3rd.

Approx. 

2.2

4th.

Approx. 

2.3

5th.

Approx. 

2.4

1W

IG2

A/C 7.5 A fuse

Ignition switch is at 
ON position

B+



Wiring harness: 
continuity, short circuit 
(Front climate control 
unit-fuse: 1W-A/C 7.5 
A)  



A/C 7.5 A fuse  

Ignition switch is at 
LOCK position

1.0 or 
less

1X

Ground

Body ground

Under any 
condition: Inspect 
for continuity to 
ground

1.0 or 

less



Wiring harness: 
continuity (Front 
climate control unit-
ground: 1X-ground)  

2A

ECT sensor 
signal

Instrument cluster

Because this terminal is for 
communication, good/no 
good judgment by terminal 
voltage is not possible.

-

2B

+5V



Driver-side 
front air mix 
actuator  



Passenger-
side front air 
mix actuator 



Front 
airflow 
mode 
actuator  



Solar 
radiation 

Under any 
condition

5.0



Wiring harness: short 
circuit (Front climate 
control unit-driver-side 
front air mix actuator, 
passenger-side front air 
mix actuator, front 
airflow mode actuator, 
solar radiation sensor, 
rear air mix actuator, 
rear airflow mode 
actuator: 2B-A, A, A, 
C, A, A)  



Driver-side front air 
mix actuator  



Passenger-side front 

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:12:36 AM

Page 40 

© 2005 Mitchell Repair Information Company, LLC. 

sensor  



Rear air mix 
actuator  



Rear airflow 
mode 
actuator  

air mix actuator  



Front airflow mode 
actuator  



Solar radiation sensor  



Rear air mix actuator  



Rear airflow mode 
actuator  

2C

Information 
display signal

Information 
display

Because this terminal is for 
communication, good/no 
good judgment by terminal 
voltage is not possible.

-

2D

Potentiometer 
input

Rear airflow mode 
actuator

Temperature control 
dial (rear side): 
Moving towards 
COLD

Approx. 

0.5



Wiring harness: 
continuity, short circuit 
(Front climate control 
unit-rear airflow mode 
actuator: 2D-E)  



Rear airflow mode 
actuator  



Front climate control 
unit: terminal voltage 
(2B)  

Temperature control 
dial (rear side): 
Moving towards 
medium 
temperature

Approx. 
2.4

Temperature control 
dial (rear side): 
Moving towards 
HOT

Approx. 

4.3

2E

Potentiometer 
input

Front airflow 
mode actuator

Mode switch: 
Moving towards 
VENT

Approx. 

1.0



Wiring harness: 
continuity, short circuit 
(Front climate control 
unit-front airflow 
mode actuator: 2E-E)  



Front airflow mode 
actuator  



Front climate control 
unit: terminal voltage 
(2B)  

Mode switch: 
Moving towards BI-
LEVEL

Approx. 
1.9

Mode switch: 
Moving towards 
HEAT

Approx. 

2.5

Mode switch: 
Moving towards 
HEAT/DEF

Approx. 

3.3

Defroster switch on

Approx. 

4.0

2F

Potentiometer 
input

Driver-side front 
air mix actuator

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

4.0



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



Driver-side front air 

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:12:36 AM

Page 41 

© 2005 Mitchell Repair Information Company, LLC.