Mazda CX-9 Grand Touring. Manual - part 238

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

VISUALLY INSPECT HO2S WIRING 
HARNESS 

 



Turn the ignition switch off.  



Disconnect the HO2S connector.  



Visually inspect the HO2S wiring 
harness. 



Check the connector (both 
halves) for contamination  



Make sure the connector pins 
are fully seated  



Is a concern present?  

NOTE:



Disconnect the HO2S wiring 
harness connector.  

Yes Repair if necessary. Go to Step 9.

No

Go to the next step.

4

INSPECT WHETHER HO2S SIGNAL 
LEVEL IS TOO HIGH  



Connect the HO2S connector.  



Turn the ignition switch to the ON 
position (Engine running)  



Access the PCM and monitor the 
HO2S signal PID.  



Is the voltage less than 1.1V?  

Yes Go to Step 6.

No

Go to the next step.

PERFORM THOROUGH WIGGLE 
TEST ON HO2S WIRING HARNESS  



Turn the ignition switch off.  



Turn the ignition switch to the ON 

Yes Repair if necessary. Go to Step 9.

 

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 85 

© 2005 Mitchell Repair Information Company, LLC. 

5

position (Engine off)  



Access the PCM and monitor the 
HO2S signal PID.  



Perform a thorough wiggle test on the 
HO2S wiring harness.  



Does the voltage change during the 
wiggle test?  

No

Perform the "INTERMITTENT CONCERN 

TROUBLESHOOTING". Then go to the next 

step.

6

INSPECT HO2S CIRCUIT FOR SHORT 
TO POWER SUPPLY IN WIRING 
HARNESS  



Turn the ignition switch off.  



Disconnect the PCM connector.  



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



Measure the voltage between HO2S 
terminal B and body ground.  



Is any voltage present?  

Yes

Repair or replace suspected part, Then go to the 
next step.

No

Go to Step 9.

7

INSPECT HO2S  



For DTC P0132 Inspect the front 
HO2S(RH)  



For DTC P0138 Inspect the rear 
HO2S(RH)  



For DTC P0152 Inspect the front 
HO2S(LH)  



For DTC P0138 Inspect the rear 
HO2S(LH) 

(See FRONT HEATED OXYGEN 
SENSOR (HO2S) INSPECTION 
[MZI-3.7] .) 

(See REAR HEATED OXYGEN 
SENSOR (HO2S) INSPECTION 
[MZI-3.7] .) 



Is there any malfunction?  

Yes

Replace the HO2S. 
(See FRONT HEATED OXYGEN SENSOR 
(HO2S) REMOVAL/INSTALLATION [MZI-
3.7] .) 
(See REAR HEATED OXYGEN SENSOR 
(HO2S) REMOVAL/INSTALLATION [MZI-
3.7] .) 
Then go to the next step.

No

Go to the next step.

8

INSPECT FOR CORRECT PCM 
OPERATION  



Disconnect all the PCM connectors.  



Visually inspect for: 

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 86 

© 2005 Mitchell Repair Information Company, LLC. 

DTC P0133, P0139, P0153, P0159 [MZI-3.7] 

DTC P0133, P0139, P0153, P0159 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES 



Pushed out pins  



Corrosion  



Connect all the PCM connectors and 
verify that they seat correctly.  

No

Repair if necessary. Then go to the next step.

9

VERIFY TROUBLESHOOTING OF 
MISFIRE DTC 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 run it at idle.  



Retrieve DTCs using the M-MDS.  



Is the PENDING CODE for this DTC 
present?  

Yes

Replace 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 P0133

P0133: Front HO2S (RH) circuit slow response

DTC P0139

P0139: Rear HO2S (RH) circuit slow response

DTC P0153

P0153: Front HO2S (LH) circuit slow response

DTC P0159

P0159: Rear HO2S (LH) circuit slow response

DETECTION 

CONDITION 



The HO2S monitor checks the HO2S frequency and amplitude.  



The test fails if the frequency and amplitude fall below a calibrated limit during 
testing.  



Contaminated HO2S  



Exhaust leaks  



Open circuit in wiring harness between PCM terminal 2Y (wiring harness-side) 
and front HO2S (RH) terminal B (wiring harness-side)  



Open circuit in wiring harness between PCM terminal 2BG (wiring harness-side) 

 

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 87 

© 2005 Mitchell Repair Information Company, LLC. 

POSSIBLE CAUSE 

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



Open circuit in wiring harness between PCM terminal 2U (wiring harness-side) 
and front HO2S (LH) terminal B (wiring harness-side)  



Open circuit in wiring harness between PCM terminal 2BC (wiring harness-side) 
and rear HO2S (LH) terminal B (wiring harness-side)  



Open circuit in wiring harness between PCM terminal 2AL (wiring harness-side) 
and HO2S terminal D (wiring harness-side)  



Short to ground in wiring harness between PCM terminal 1BJ (wiring harness-
side) and PCM terminal 2Y (wiring harness-side)  



Short to ground in wiring harness between PCM terminal 1BJ (wiring harness-
side) and PCM terminal 2BG (wiring harness-side)  



Short to ground in wiring harness between PCM terminal 1BJ (wiring harness-
side) and PCM terminal 2U (wiring harness-side)  



Short to ground in wiring harness between PCM terminal 1BJ (wiring harness-
side) and PCM terminal 2BC (wiring harness-side)  



Short to ground in wiring harness between HO2S terminal A (wiring harness-
side) and battery negative terminal  



Short to ground in wiring harness between HO2S terminal A (wiring harness-
side) and HO2S terminal C (wiring harness-side)  



Short to ground in wiring harness between HO2S terminal A (wiring harness-
side) and HO2S terminal D (wiring harness-side)  



Short to ground in wiring harness between HO2S terminal A (wiring harness-
side) and HO2S terminal B (wiring harness-side)  



Short to ground in wiring harness between PCM terminal 2J and front HO2S 
(RH) terminal A  



Short to ground in wiring harness between PCM terminal 2E and front HO2S 
(RH) terminal A  



Short to ground in wiring harness between PCM terminal 2AO and rear HO2S 
(LH) terminal A  



Short to ground in wiring harness between PCM terminal 2AS and rear HO2S 
(LH) terminal A  



Incorrect fueling  



MAF sensor malfunction  



Deteriorating HO2S  



Inlet air leaks  

 

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 88 

© 2005 Mitchell Repair Information Company, LLC.