Mazda CX-9 Grand Touring. Manual - part 239

 

2008 Mazda CX-9 Grand Touring 

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

  

Microsoft 

 

Sunday, November 15, 2009 10:08:35 AM

Page 89 

© 2005 Mitchell Repair Information Company, LLC. 

DIAGNOSTIC PROCEDURE 

DTC P0133, P0139, P0153, P0159 (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

PERFORM KOER SELF-TEST  



Verify that the engine is at normal 
operating temperature.  



Perform the KOER self-test.  



Are DTCs P0040, P0041 or P1127 
present?  

Yes

Go to the appropriate DTC troubleshooting. 
(See DTC TABLE [MZI-3.7].)

No

Go to the next step.

4

INSPECT FOR UNMETERED AIR 
LEAKS 

 



Carefully inspect the following areas 
for potential air leaks: 



Hoses connecting to the MAF 
sensor assembly  



Hoses connecting to the throttle 
body  



Intake manifold gasket leaks  



PCV system  



The vacuum lines are 
disconnected  



Improperly seated engine oil 
dipstick, tube or oil filler cap  

NOTE:



Fuel calculations can be affected by 
unmetered air leaks.  

Yes

Repair the source of the air leak. Then go to 
Step 17.

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 10:08:35 AM

Page 90 

© 2005 Mitchell Repair Information Company, LLC. 



Exhaust leaks at flanges and 
gaskets  



Are any air leaks present?  

5

INSPECT HO2S CIRCUIT (S) FOR 
OPEN CIRCUIT IN WIRING HARNESS 



Turn the ignition switch off.  



Remove the jumper wire (s).  



Visually inspect the HO2S wiring 
harness for exposed wiring, water 
contamination, corrosion, and proper 
assembly.  



Disconnect the PCM connector.  



Measure the resistance between the 
following terminals: 



PCM terminal 2Y (wiring 
harness-side) and front HO2S 
(RH) terminal B (wiring harness-
side)  



PCM terminal 2BG (wiring 
harness-side) and rear HO2S 
(RH) terminal B (wiring harness-
side)  



PCM terminal 2U (wiring 
harness-side) and front HO2S 
(LH) terminal B (wiring harness-
side)  



PCM terminal 2BC (wiring 
harness-side) and rear HO2S 
(LH) terminal B (wiring harness-
side)  



PCM terminal 2AL (wiring 
harness-side) and HO2S terminal 
D (wiring harness-side)  



Are the resistances less than 5 ohms?  

Yes Go to the next step.

No

Repair or replace suspected part, Then go to 

Step 17.

INSPECT HO2S CIRCUIT FOR SHORT 
TO POWER SUPPLY  



Measure the resistance between the 
following terminals: 



PCM terminal 1BJ (wiring 
harness-side) and PCM terminal 
2Y (wiring harness-side)  

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 10:08:35 AM

Page 91 

© 2005 Mitchell Repair Information Company, LLC. 

6



PCM terminal 1 BJ (wiring 
harness-side) and PCM terminal 
2BG (wiring harness-side)  



PCM terminal 1 BJ (wiring 
harness-side) and PCM terminal 
2U (wiring harness-side)  



PCM terminal 1BJ (wiring 
harness-side) and PCM terminal 
2BC (wiring harness-side)  



Is the resistance more than 10 kilohms? 

No

Go to Step 10.

7

INSPECT FOR SOURCE OF 
POTENTIAL HO2S CONTAMINATION 



Investigate the following items as 
potential sources of HO2S 
contamination: 



Use of unapproved silicon sealers 



Fuel contaminated by silicon 
additives  



Excessive oil consumption  



Glycol leaking internally in the 
engine  



Lead-contaminated fuel  



Short drive cycles in cold weather 



Use of unapproved cleaning 
agents  



Is a concern present?  

Yes

Repair the source of the contamination. Change 
the engine oil and oil filter. Then go to Step 17.

No

Go to the next step.

8

VISUALLY INSPECT HO2S WIRING 
HARNESS  



Connect the PCM connector.  



Visually inspect the HO2S wiring 
harness for exposed wiring water 
contamination, corrosion, and proper 
assembly.  



Is a concern present?  

Yes Repair if necessary. Then go to the next step.

No

Go to the next step.

INSPECT HO2S AND SIGRTN 
CIRCUITS FOR OPEN CIRCUIT IN 
WIRING HARNESS 

NOTE:



Verify the wiring harness terminals 

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 10:08:35 AM

Page 92 

© 2005 Mitchell Repair Information Company, LLC.