Mazda CX-9 Grand Touring. Manual - part 268

DIAGNOSTIC PROCEDURE 

DTC P0443 (MZI-3.7) DIAGNOSTIC PROCEDURE 

POSSIBLE CAUSE 



Purge solenoid valve malfunction  



Connector or terminal malfunction  



Short to ground between purge solenoid valve terminal B and PCM terminal 1 BC  



Open circuit between main relay No.1 terminal D and purge solenoid valve terminal
A  



Short to power supply between purge solenoid valve terminal B and PCM terminal 
1 BC  



Open circuit between purge solenoid valve terminal B and PCM terminal 1 BC  



PCM malfunction  

STEP

INSPECTION

ACTION

VERIFY FREEZE FRAME DATA 
HAS BEEN RECORDED  

Yes Go to the next step.

 

2008 Mazda CX-9 Grand Touring 

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:08:37 AM

Page 205 

© 2005 Mitchell Repair Information Company, LLC. 

1



Has FREEZE FRAME DATA been 
recorded?  

No

Record FREEZE FRAME DATA on the repair 

order, then go to the next step.

2

VERIFY RELATED REPAIR 
INFORMATION AVAILABILITY  



Verify related Service Bulletins 
and/or on-line repair information 
availability.  



Is any related Service Bulletins 
available?  

Yes

Perform repair or diagnosis according to the 
available Service Bulletins. 



If the vehicle is not repaired, go to the next 
step.  

No

Go to the next step.

3

INSPECT PURGE SOLENOID 
VALVE CONNECTOR FOR POOR 
CONNECTION  



Turn the ignition switch off.  



Disconnect purge solenoid valve 
connector.  



Inspect for poor connection (such 
as damaged/pulled-out pins, 
corrosion).  



Are there any malfunction?  

Yes

Repair or replace suspected part, then go to Step 
10.

No

Go to the next step.

4

INSPECT POWER SUPPLY 
CIRCUIT FOR OPEN CIRCUIT  



Turn the ignition switch to the ON 
position (Engine off).  



Measure voltage between purge 
solenoid valve terminal A and body 
ground.  



Is voltage B+?  

Yes Go to the next step.

No

Repair or replace suspected part, then go to Step 

10.

5

INSPECT PURGE SOLENOID 
VALVE CONTROL CIRCUIT FOR 
SHORT TO POWER SUPPLY  



Turn the ignition switch to the ON 
position (Engine off).  



Measure the voltage between purge 
solenoid valve control terminal B 
and body ground.  



Is voltage B+?  

Yes

Repair or replace suspected part, then go to Step 
10.

No

Go to the next step.

INSPECT PURGE SOLENOID 
VALVE CONTROL CIRCUIT FOR 
SHORT TO GROUND  

Yes

Repair or replace suspected part, then go to the 

 

2008 Mazda CX-9 Grand Touring 

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:08:37 AM

Page 206 

© 2005 Mitchell Repair Information Company, LLC. 

6



Turn the ignition switch off.  



Inspect for continuity between 
purge solenoid valve control 
terminal B and body ground.  



Is there continuity?  

Step 10.

No

Go to the next step.

7

INSPECT PCM CONNECTOR FOR 
POOR CONNECTION  



Turn the ignition switch off.  



Disconnect PCM connector.  



Inspect for poor connection (such 
as damaged/pulled-out pins, 
corrosion).  



Is there any malfunction? v  

Yes

Repair or replace suspected part, then go to Step 
10.

No

Go to the next step.

8

INSPECT PURGE SOLENOID 
VALVE CONTROL CIRCUIT FOR 
OPEN CIRCUIT  



Turn the ignition switch off.  



Inspect continuity between purge 
solenoid valve terminal B and PCM 
terminal 1BC.  



Is there continuity?  

Yes Go to the next step.

No

Repair or replace suspected part, then go to the 

Step 10.

9

INSPECT PURGE SOLENOID 
VALVE  



Inspect the purge solenoid valve. 
(See PURGE SOLENOID 
VALVE INSPECTION [MZI-
3.7] .)  



Is there any malfunction?  

Yes

Replace purge solenoid valve (See PURGE 
SOLENOID VALVE 
REMOVAL/INSTALLATION [MZI-3.7] .), then 
go to Step 10.

No

Go to the next step.

10

VERIFY TROUBLESHOOTING OF 
DTC P0443 COMPLETED  



Make sure to reconnect all 
disconnected connectors.  



Clear DTC from PCM memory 
using M-MDS.  



Perform the "KOEO or KOER self-
test" using the M-MDS. (See 
KOEO/KOER SELF TEST 
[MZI-3.7].)  



Is the PENDING CODE same DTC 

Yes

Replace PCM, then go to the next step. (See PCM 
REMOVAL/INSTALLATION [MZI-3.7] .)

No

Go to the next step.

 

2008 Mazda CX-9 Grand Touring 

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:08:38 AM

Page 207 

© 2005 Mitchell Repair Information Company, LLC. 

DTC P0446 [MZI-3.7] 

DTC P0446 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES 

present?  

11

VERIFY AFTER REPAIR 
PROCEDURE  



Perform the "AFTER REPAIR 
PROCEDURE". (See AFTER 
REPAIR PROCEDURE [MZI-
3.7].)  



Are any DTCs present?  

Yes

Go to the applicable DTC inspection. (See DTC 
TABLE [MZI-3.7].)

No

Troubleshooting completed.

DTC P0446

CV solenoid valve control circuit

DETECTION 

CONDITION 



Monitors the CV solenoid valve circuit for an electrical failure. The test fails when 
the signal moves outside the minimum or maximum allowable calibrated parameters 
for a specified canister vent duty cycle by PCM command.  

POSSIBLE 

CAUSE 



CV solenoid valve malfunction  



Connector or terminal malfunction  



Short to ground between CV solenoid valve terminal B and PCM terminal 1Z  



Open circuit between battery and CV solenoid valve terminal A  



Short to power supply between CV solenoid valve terminal B and PCM terminal 1Z 



Open circuit between CV solenoid valve terminal B and PCM terminal 1Z  



PCM malfunction  

 

2008 Mazda CX-9 Grand Touring 

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:08:38 AM

Page 208 

© 2005 Mitchell Repair Information Company, LLC.