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.