Mazda CX-9 Grand Touring 2009 Manual page 1755

When performing an asterisked (*) troubleshooting inspection, shake the wiring harness and connectors
while doing the inspection to discover whether poor contact points are the cause of any intermittent
malfunctions. If there is a problem, inspect to make sure connectors, terminals and wiring harness are
connected correctly and undamaged.
DIAGNOSTIC PROCEDURE
NO.5 WINDSHIELD FOGGED DIAGNOSTIC PROCEDURE
STEP
COOL AIR BLOW OUT INSPECTION
1
When both the A/C and fan switch in the front
climate control unit are on, does cool air blow out
from the front vent?
INSPECT FRONT CLIMATE CONTROL UNIT
POWER SUPPLY FUSE FOR B+ SIGNAL
2
Is the front climate control unit power supply fuse
for B+ signal normal?
INSPECT AIR INTAKE ACTUATOR
Inspect the air intake actuator for followings.
Is there grease on the link?
3
Is the link securely and properly positioned?
Is the link free of obstructions?
Are the above items normal?
INSPECT WIRING HARNESS BETWEEN FUSE
BLOCK AND FRONT CLIMATE CONTROL UNIT
FOR CONTINUITY
Disconnect the front climate control unit connector
*4
(24-pin).
Turn the ignition switch to the ON position.
Measure the voltage at front climate control unit
terminal 1B (B+ signal).
Is the voltage approx. 12 V?
INSPECT WIRING HARNESS BETWEEN FRONT
CLIMATE CONTROL UNIT AND GROUND FOR
VOLTAGE
*5
Measure the voltage at front climate control unit
terminal 1X (Ground).
Is the voltage approx. 0 V?
2008 Mazda CX-9 Grand Touring
2008 HVAC Symptom Troubleshooting (HVAC) - Mazda CX-9
INSPECTION ACTION
Yes Go to the next step.
Go to Step 1 of troubleshooting
No
index No.8.
Yes Go to the next step.
Inspect for a short to ground on
blown fuse circuit.
No
Repair or replace if necessary.
Install appropriate amperage fuse.
Yes Go to the next step.
Apply grease or install the link
No properly and securely, remove
obstruction, then go to Step 14.
Yes Go to the next step.
Repair the wiring harness between
No the fuse block and front climate
control unit, then go to Step 14.
Yes Go to the next step.
Repair the wiring harness between
No the front climate control unit and
ground, then go to Step 14.