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.