Mazda CX-9 Grand Touring. Manual - part 301

DTC P145E [MZI-3.7] 

DTC P145E (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES 

8



Connect all disconnected connectors 
and hoses.  



Perform the EVAP system leak test. 
(See ENGINE CONTROL 
SYSTEM OPERATION 
INSPECTION [MZI-3.7] .)  



Are the test results normal?  

Yes Go to the next step.

No

Leakage still exists. Locate leak point and repair. 

Repeat this step.

9

VERIFY TROUBLESHOOTING OF 
DTC P1450 HAS BEEN COMPLETED 



Verify that all disconnected 
connectors are reconnected.  



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



Clear the DTC from the PCM 
memory using the M-MDS.  



Start the engine and the perform 
"EVAP system monitor drive cycle" 



Retrieve DTCs using the M-MDS.  



Is the PENDING CODE for this 
DTC present?  

Yes

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

No

Go to the next step.

10

VERIFY AFTER REPAIR 
PROCEDURE  



Perform "AFTER REPAIR 
PROCEDURE".  



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



Are any DTC present?  

Yes

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

No

Troubleshooting completed.

DTC P145E

PCV heater control circuit

DETECTION 

CONDITION 



This DTC sets when the PCM detects a PCV valve heater circuit malfunction.



Open circuit between PCV valve heater control terminal A and main relay 
No.1  



Open circuit between PCV valve heater fitting terminal A and main relay 
No.1  



Short to ground circuit between PCV valve heater control terminal B and 
PCM terminal 2BL  

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:08:41 AM

Page 337 

© 2005 Mitchell Repair Information Company, LLC. 

POSSIBLE CAUSE 



Short to ground circuit between PCV valve heater fitting terminal B and PCM
terminal 2AU  



Open circuit between PCV valve heater control terminal B and PCM terminal 
2BL  



Open circuit between PCV valve heater fitting B and PCM terminal 2AU  



Connector or terminal malfunction  



PCV valve heater control malfunction  



PCV valve heater fitting malfunction  

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:08:41 AM

Page 338 

© 2005 Mitchell Repair Information Company, LLC. 

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:08:41 AM

Page 339 

© 2005 Mitchell Repair Information Company, LLC. 

DIAGNOSTIC PROCEDURE 

DTC P145E (MZI-3.7) DIAGNOSTIC PROCEDURE 

STEP

INSPECTION

ACTION

1

VERIFY FREEZE FRAME DATA HAS 
BEEN RECORDED  



Has FREEZE FRAME DATA been 
recorded?  

Yes Go to the next step.

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 PCV VALVE HEATER 
CONTROL AND PCV VALVE HEATER 
FITTING CONNECTOR FOR POOR 
CONNECTION  



Turn the ignition switch off.  



Disconnect PCV valve heater control and 
PCV valve heater fitting 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 9.

No

Go to the next step.

4

INSPECT POWER SUPPLY CIRCUIT 
FOR OPEN CIRCUIT  



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



Inspect the voltage between the following 
circuit: 



PCV valve heater control terminal 
A (wiring harness-side) and body 
ground  



PCV valve heater fitting terminal A 
(wiring harness-side) and body 
ground  



Are there voltage B+?  

Yes Go to the next step.

No

Repair or replace suspected part, then go to 

Step 9.

INSPECT PCV VALVE HEATER 
CONTROL AND PCV VALVE HEATER 
FITTING CIRCUIT FOR SHORT TO 
GROUND  

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:08:41 AM

Page 340 

© 2005 Mitchell Repair Information Company, LLC.