Mazda CX-9 Grand Touring 2009 Manual page 1768

When performing an asterisked (*) troubleshooting inspection, shake the wiring harness and connectors
while performing the inspection to discover whether poor contact points are the cause of any intermittent
malfunctions. If there is a problem, check to make sure connectors, terminals and wiring harnesses are
connected correctly and undamaged.
DIAGNOSTIC PROCEDURE
NO.9 NO COOL AIR FROM FRONT/REAR VENTS DIAGNOSTIC PROCEDURE
STEP
INSPECT AIR FLOW FROM VENTS
1
Does air blow out?
INSPECT A/C COMPRESSOR OPERATION
Start engine.
2
Turn A/C switch and fan switch on.
Does A/C compressor operate?
INSPECT FOR DTC IN PCM
Inspect for DTCs related to the PCM onboard
3
diagnostic system.
Are any DTCs displayed?
INSPECT TO SEE WHETHER
MALFUNCTION IS IN CLIMATE CONTROL
UNIT OR ELSEWHERE
4
Does cool air blow out when terminal 1S of
climate control unit connector (24-pin, A/C
signal) is grounded?
INSPECT TO SEE WHETHER
MALFUNCTION IS IN A/C SIGNAL
CIRCUIT (BETWEEN REFRIGERANT
PRESSURE SWITCH AND PCM) OR
ELSEWHERE
5*
Test voltage at following terminal of
refrigerant pressure switch.
Terminal B (A/C signal)
Is voltage approx. 12 V?
2008 Mazda CX-9 Grand Touring
2008 HVAC Symptom Troubleshooting (HVAC) - Mazda CX-9
Malfunction in A/C relay
Malfunction in evaporator temperature sensor
Malfunction in BCM unit
INSPECTION ACTION
Yes Go to the next step.
Go to Step 1 of troubleshooting indexes
No
No.1 and 2.
Go to Step 1 of troubleshooting index
Yes
No.7.
No Go to the next step.
Yes Go to appropriate inspection procedure.
No Go to the next step.
Replace climate control unit, then go to
Yes
Step 16.
No Release short, then go to the next step.
Yes Go to Step 7.
No Go to the next step.