Mazda CX-9 Grand Touring. Manual — part 443

6*

INSPECT TO SEE WHETHER
MALFUNCTION IS IN WIRING HARNESS
(BETWEEN REFRIGERANT PRESSURE
SWITCH AND PCM) OR PCM



Test voltage at A/C signal terminal of PCM.



Is voltage approx. 12 V?

Yes

Repair wiring harness between PCM and
refrigerant pressure switch, then go to
Step 16.

No

Inspect PCM, then go to Step 16.

7

INSPECT TO SEE WHETHER
MALFUNCTION IS IN REFRIGERANT
PRESSURE SWITCH, REFRIGERANT
AMOUNT, OR ELSEWHERE



Does cool air blow out when terminals B and
C of refrigerant pressure switch connector are
shorted?

Yes Go to the next step.

No

Go to Step 9.

8

INSPECT TO SEE WHETHER
MALFUNCTION IS IN REFRIGERANT
PRESSURE SWITCH OR REFRIGERANT
AMOUNT



Inspect refrigerant pressure switch.



Is it okay?

Yes

If refrigerant amount is empty, replace
condenser, vacuum refrigerant line more
than 30 min by vacuum pump, and add
refrigerant to specified level, then go to
Step 16.

No

Replace refrigerant pressure switch, then

go to Step 16.

9

INSPECT TO SEE WHETHER
MALFUNCTION (SHORT CIRCUIT) IS IN
A/C CONTROL SIGNAL CIRCUIT
(BETWEEN A/C RELAY AND PCM) OR
ELSEWHERE



Does cool air blow out when terminal A of
A/C relay connector (A/C control signal) is
grounded?

Yes Release short, then go to the next step.

No

Go to Step 11.

10*

INSPECT TO SEE WHETHER
MALFUNCTION (OPEN OR SHORT
CIRCUIT) IS IN PCM OR WIRING HARNESS
(BETWEEN A/C RELAY AND PCM)



Test voltage at the A/C relay control signal
terminal of PCM.



Is voltage approx. 12 V?

Yes Inspect PCM, then go to Step 16.

No

Repair wiring harness between A/C relay

and PCM, then go to Step 16.

11*

INSPECT TO SEE WHETHER
MALFUNCTION IS IN MAGNETIC CLUTCH
OR ELSEWHERE



Test voltage at the following terminal of
magnetic clutch thermal protector.

Yes

Inspect magnetic clutch, then go to Step
16.

2008 Mazda CX-9 Grand Touring

2008 HVAC Symptom Troubleshooting (HVAC) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:14:51 AM

Page 28

© 2005 Mitchell Repair Information Company, LLC.

NO.10 NOISE WHILE OPERATING A/C SYSTEM.

NO.10 NOISE WHILE OPERATING A/C SYSTEM DESCRIPTION AND POSSIBLE CAUSE



Terminal B (magnetic clutch operation
signal)



Is voltage approx. 12 V?

No

Go to the next step.

12

INSPECT FUSE



Are A/C relay power supply fuses okay?

Yes Go to the next step.

No

Replace fuse, then go to Step 16. If fuse

burns out immediately, go to the next

step.

13

INSPECT WIRING HARNESS BETWEEN
FUSE BLOCK AND A/C RELAY FOR LACK
OF CONTINUITY



Test voltages at following terminals of A/C
relay.



Terminal E (A/C relay control signal)



Terminal C (A/C control signal)



Are voltages approx. 12 V?

Yes Go to the next step.

No

Repair wiring harness between fuse block

and A/C relay, then go to Step 16.

14

INSPECT TO SEE WHETHER
MALFUNCTION IS IN A/C RELAY OR
WIRING HARNESS (BETWEEN A/C RELAY
AND MAGNETIC CLUTCH) AND
EVAPORATOR TEMPERATURE SENSOR



Test voltage at the following terminal of A/C
relay.



Terminal D (magnetic clutch operation
signal)



Is voltage approx. 12 V?

Yes

Inspect wiring harness between A/C relay
and magnetic clutch.



If above wiring harness is OK, go
to the next step.



If above wiring harness
malfunctions, repair wiring harness,
then go to Step 16.

No

Replace A/C relay, then go to Step 16.

15

INSPECT EVAPORATOR TEMPERATURE
SENSOR



Inspect evaporator temperature sensor.



Is it okay?

Yes Go to the next step.

No

Replace evaporator temperature sensor,

then go to the next step.

16

VERIFY REPAIR



Does cool air blow out from front/rear vents?
(Are the results of refrigerant system
performance test okay?)

Yes

Troubleshooting completed. Explain
repairs to customer.

No

Recheck malfunction symptoms, then

repeat from Step 1 if malfunction recurs.

10

Noise while operating A/C system.



Problem with A/C basic system installation

2008 Mazda CX-9 Grand Touring

2008 HVAC Symptom Troubleshooting (HVAC) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:14:51 AM

Page 29

© 2005 Mitchell Repair Information Company, LLC.

DIAGNOSTIC PROCEDURE

NO.10 NOISE WHILE OPERATING A/C SYSTEM DIAGNOSTIC PROCEDURE

DESCRIPTION



Noise from magnetic clutch, A/C compressor, hose or refrigerant line.

POSSIBLE CAUSE



Magnetic clutch operation noise



A/C compressor vane noise



A/C compressor slippage noise



Hose or refrigerant line interference noise

STEP

INSPECTION

ACTION

1

CHECK A/C COMPRESSOR VANE
NOISE



Is there a jingling, popping, beeping,
or buzzing sound (A/C compressor
vane noise)?

Yes Go to Step 5.

No

Go to the next step.

2

INSPECT A/C COMPRESSOR
SLIPPAGE NOISE



Is there a squeaking or whirling
sound (A/C compressor slippage
noise)?

Yes Go to Step 14.

No

Go to the next step.

3

INSPECT A/C COMPRESSOR
INTERFERENCE NOISE



Is there a rattling or vibrating sound
(interference noise)?

Yes Go to Step 18.

No

Go to the next step.

4

INSPECT MAGNETIC CLUTCH
OPERATION NOISE



Is there a clicking sound (magnetic
clutch operation noise)?

Yes

Adjust clearance between pressure plate of
magnetic clutch and A/C compressor pulley, then
go to Step 19.
(See MAGNETIC CLUTCH
ADJUSTMENT .)

No

Condition is normal. (Recheck malfunction

symptoms.)

5

INSPECT A/C COMPRESSOR NOISE
TIME



Is noise heard continuously for more
than 3 s after A/C compressor comes
on?

Yes Go to the next step.

No

Condition is normal. (Noise occurs for 2-3 s

immediately after A/C compressor turns on.)

INSPECT IDLE SPEED



Inspect idle speed.

Yes Go to the next step.

2008 Mazda CX-9 Grand Touring

2008 HVAC Symptom Troubleshooting (HVAC) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:14:51 AM

Page 30

© 2005 Mitchell Repair Information Company, LLC.

6

(See ENGINE TUNE-UP [MZI-
3.7] .)



Is it okay?

No

Follow the repair instruction described in section

01, then go to Step 19.

7

INSPECT REFRIGERANT AMOUNT



Inspect refrigerant amount.



Is it okay?

Yes Go to Step 10.

No

Go to the next step.

8

INSPECT REFRIGERANT LINES



Inspect refrigerant lines.



Is piping free of damage and
cracks?



Are piping connections free of
oil grime? (Visual inspection)



Are piping connections free of
gas leakage?



Are piping installation points
on condenser free of gas
leakage?



Are piping installation points
on receiver/drier free of gas
leakage?



Are piping installation points
on A/C compressor free of gas
leakage?



Are piping installation points
on A/C unit free of gas leakage



Perform gas leak inspection
using gas leak tester.



Are above items okay?

Yes Go to the next step.

No

If piping or A/C component(s) is damaged or

cracked, replace then go to Step 19.

If there is gas leakage, repair or replace

connection and replace condenser

(1)

, then go to

Step 19.

9

INSPECT EVAPORATOR PIPING
CONNECTIONS IN A/C UNIT FOR
GAS LEAKAGE



Are piping connections for
evaporator in A/C unit free of gas
leakage?

Yes

Adjust refrigerant amount to specified level, then
go to Step 19.

No

If piping is damaged or cracked, replace then go

to Step 19. If there is gas leakage, repair or

replace connection and replace condenser

(1)

, then

go to Step 19.

10

CHECK TO SEE WHETHER
MALFUNCTION IS IN
COMPRESSOR OIL OR
ELSEWHERE



Add 20 ml {20 cc, 0.8 fl oz} of

Yes Go to the next step.

No

Troubleshooting completed.

2008 Mazda CX-9 Grand Touring

2008 HVAC Symptom Troubleshooting (HVAC) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:14:51 AM

Page 31

© 2005 Mitchell Repair Information Company, LLC.