Mazda CX-9 Grand Touring. Manual — part 241

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 97

© 2005 Mitchell Repair Information Company, LLC.

DIAGNOSTIC PROCEDURE

DTC P0135, P0141, P0155, P0161 (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 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 the next
step.

No

Go to the next step.

4

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 or replace suspected part, Then go to
Step 12.

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 98

© 2005 Mitchell Repair Information Company, LLC.

5

INSPECT POWER SUPPLY IN WIRING
HARNESS



Disconnect suspect HO2S connector.



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



Measure the voltage between suspect
HO2S connector terminal A and C, on
the wiring harness side.



Is the voltage more than 10 V?

Yes

Turn the ignition switch off. Go to the next
step.

No Repair or replace suspected part, Go to Step 12.

6

INSPECT HO2S HEATER FOR SHORT
TO GROUND



Disconnect the PCM connector.



Measure the resistance between HO2S
terminal A on the wiring harness side
and body ground.



Is the resistance more than 10 kilohms?

Yes Go to the next step.

No Repair or replace suspected part, Go to Step 12.

7

INSPECT HO2S HEATER FOR SHORT
IN WIRING HARNESS



Measure the resistance between the
following terminals:



HO2S terminal A (wiring
harness-side) and HO2S terminal
C (wiring harness-side)



HO2S terminal A (wiring
harness-side) and HO2S terminal
D (wiring harness-side)



HO2S terminal A (wiring
harness-side) and HO2S terminal
B (wiring harness-side)



Are the resistances more than 10
kilohms?

Yes Go to the next step.

No Repair or replace suspected part, Go to Step 12.

8

INSPECT HO2S HEATER CIRCUIT
FOR OPEN CIRCUIT IN WIRING
HARNESS



For DTC P0135, measure the resistance
between PCM terminal 2J and front
HO2S (RH) terminal A.



For DTC P0141, measure the resistance
between PCM terminal 2AS and rear
HO2S (RH) terminal A.

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 99

© 2005 Mitchell Repair Information Company, LLC.



For DTC P0155, measure the resistance
between PCM terminal 2E and front
HO2S (LH) terminal A.



For DTC P0161, measure the resistance
between PCM terminal 2AO and rear
HO2S (LH) terminal A.



Is the resistance less than 5.0 ohms?

No Repair or replace suspected part, Go to Step 12.

9

INSPECT INTERNAL RESISTANCE OF
HO2S HEATER



Measure the resistance between the
suspect HO2S terminal A and C, on the
component side.



Is the resistance between 3-30 ohms?

Yes Go to the next step.

No

Replace HO2S.

(See FRONT HEATED OXYGEN SENSOR

(HO2S) REMOVAL/INSTALLATION

[MZI-3.7] .)

(See REAR HEATED OXYGEN SENSOR

(HO2S) REMOVAL/INSTALLATION

[MZI-3.7] .)

Go to Step 12.

10

INSPECT HO2S CASE FOR SHORT TO
POWER SUPPLY, HTR, AND SIGNRTN



Measure the resistance between the
suspect HO2S terminal A and D at
component side.



Measure the resistance between the
suspect HO2S terminal A and body
ground.



Is the resistance more than 10 kilohms?

Yes Go to the next step.

No

Replace HO2S.

(See FRONT HEATED OXYGEN SENSOR

(HO2S) REMOVAL/INSTALLATION

[MZI-3.7] .)

(See REAR HEATED OXYGEN SENSOR

(HO2S) REMOVAL/INSTALLATION

[MZI-3.7] .)

Go to the next step.

11

INSPECT FOR CORRECT PCM
OPERATION



Disconnect all the PCM connectors.



Visually inspect for:



Pushed out pins



Corrosion



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



Retrieve DTCs using the M-MDS.



Is the PENDING CODE for this DTC
present?

Yes Go to the next step.

No

The system is correctly. Go to the next step.

VERIFY TROUBLESHOOTING OF
MISFIRE DTC HAS BEEN
COMPLETED



Verify that all disconnected connectors

Yes

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

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 100

© 2005 Mitchell Repair Information Company, LLC.