Mazda CX-9 Grand Touring. Manual - part 267

DIAGNOSTIC PROCEDURE

DTC P0442, P0456 (MZI-3.7) DIAGNOSTIC PROCEDURE

DETECTION

CONDITION

EVAP vapor management valve solenoid system when there is less than 0.625
kPa (PID FTP_H2O displays "2.5") bleed-up over 15 s at 75% fuel fill. Bleed-up
and evaluation time vary as a function of fuel fill level. The vapor generation
limit is more than 0.625 kPa (PID FTP_H2O displays "2.5") over 120 s.



P0456 indicates that a fuel vapor leak from an opening as small as 0.508 mm
{0.020 in} has been detected by the EVAP running loss monitor test.

POSSIBLE

CAUSE



After-market EVAP hardware (such as fuel-filler cap) nonconforming to
required specifications.



Small holes or cuts in fuel vapor hoses/tubes (P0442, P0456).



CV solenoid stays partially open on closed command.



Damaged, cross-threaded or loosely installed fuel-filler cap.



EVAP system component seals leaking.

STEP

INSPECTION

ACTION

VERIFY FREEZE FRAME DATA HAS BEEN
RECORDED



Has FREEZE FRAME DATA been
recorded?

Yes Go to the next step.

Record FREEZE FRAME DATA on the

repair order, then go to the next step.

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.

Go to the next step.

VERIFY RELATED PENDING CODE OR
STORED DTCs



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



Verify related pending code or stored DTCs.



Is other DTCs present?

Yes

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

Go to the next step.

EVAP SYSTEM LEAK TEST



Carry out the EVAP system leak inspection
using the M-MDS. (See ENGINE
CONTROL SYSTEM OPERATION
INSPECTION [MZI-3.7] .)



Is small or large leakage detected?

Yes Go to the next step.

Go to Step 6.

EVAP SYSTEM LEAK TEST

2008 Mazda CX-9 Grand Touring

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

Microsoft

Sunday, November 15, 2009 10:08:37 AM

Page 201



Re-tighten the fuel-filler cap then carry out
the EVAP system leak inspection using the
M-MDS again. (See ENGINE CONTROL
SYSTEM OPERATION INSPECTION
[MZI-3.7] .)



Is small or large leakage detected?

Yes Go to the next step.

Go to Step 14.

VISUALLY INSPECT COMPONENTS FOR
SMALL LEAKS



Verify that the CV solenoid valve is
properly seated on the charcoal canister.



Visually inspect for cut or loose connections
to the fuel vapor hoses/tubes in the
following locations:



Charcoal canister to CV solenoid
valve.



Charcoal canister to evaporative
emission valve component.



Evaporative emission valve
component to the fuel tank (if
applicable).



Check for fuel-filler pipe damage.



Is a concern with a hose, tube, connection,
or valve visually evident?

Yes

Repair or install a new component if
necessary. Go to Step 13.

Go to the next step.

INSPECT FOR SMALL LEAKS AT FUEL-
FILLER CAP



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



Close CV solenoid valve using the
EVAPCV PID.



Using the EVAP system tester, check for
leaks around the fuel-filler cap.



Is a leak detected?

Yes Go to the next step.

Go to Step 9.

VISUALLY INSPECT FUEL-FILLER CAP
AND FUEL-FILLER PIPE



Visually inspect the fuel-filler cap and fuel-
filler pipe for damage.



Is the fuel-filler cap or fuel-filler pipe
damaged?

Yes

Replace the malfunctioning parts, then go
to Step 13.

Go to the next step.

INSPECT FOR SMALL LEAK WITH
TESTER SET AT FILL POSITION

2008 Mazda CX-9 Grand Touring

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

Microsoft

Sunday, November 15, 2009 10:08:37 AM

Page 202



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



Close CV solenoid valve using the
EVAPCV PID from the output test mode.



Pressurize EVAP system to 3.48 kPa (PID
FTP_H2O displays "14").



Does the pressure hold between 3.43 and
3.53 kPa (PID FTP_H2O displays "13.80"
and "14.20")?

Yes Go to Step 13.

Go to Step 10.

INSPECT FOR LEAKS IN COMPLETE
EVAP SYSTEM



Verify CV solenoid valve is closed.



Verify system is pressurized to 3.48 kPa
(PID FTP_H2O displays "14").



Using the ultrasonic leak detector, check the
following EVAP system locations:



EVAP return tube to CV solenoid
valve.



CV solenoid valve to charcoal
canister-CV solenoid valve
component.



Charcoal canister-CV solenoid valve
component to fuel tank.



fuel-filler cap and fuel-filler pipe.



Is a leak detected?

Yes

Repair or replace the component if
necessary. Go to Step 13.

Discontinue pressurizing the system. Go to

the next step.

INSPECT FOR SMALL LEAK FROM EVAP
RETURN TUBE TO CHARCOAL CANISTER



Disconnect the fuel tank vapor tube at the
fuel fuel vapor hose joint and plug the
opening in the hose joint.



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



Close CV solenoid valve using the
EVAPCV PID from the output test mode.



Pressurize the EVAP system to 3.48 kPa
(PID FTP_H2O displays "14").



Using the ultrasonic leak detector, check the
EVAP system from the intake manifold to
the CV solenoid valve.



Is a leak detected?

Yes

Repair or replace the component if
necessary. Go to Step 13.

Open the CV solenoid valve. 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 10:08:37 AM

Page 203

DTC P0443 [MZI-3.7]

DTC P0443 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES

INSPECT FOR SMALL LEAK BETWEEN
FUEL TANK VAPOR TUBE AND FUEL
TANK FILLER PIPE



Transfer the plug from the fuel vapor hose
joint to the fuel tank vapor tube.



Pressurize EVAP system to 3.48 kPa (PID
FTP_H2O displays "14").



Using the ultrasonic leak detector, check the
fuel tank vapor tube to the fuel tank for
leaks. Check the FTP sensor, fuel tank vapor
tube and the fuel-filler pipe.



Is a leak detected?

Yes

Repair or install a new component. Go to
the next step.

Reconnect the fuel vapor tube to the fuel

vapor hose joint. Go to Step 13.

EVAP SYSTEM LEAK TEST



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.

Leakage still exists. Locate leak point and

repair. Repeat this step.

VERIFY TROUBLESHOOTING OF DTC
P0442, P0456 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 the PCM, then go to the next step.
(See PCM
REMOVAL/INSTALLATION [MZI-
3.7] .)

Go to the next step.

DTC P0443

Purge solenoid valve circuit

DETECTION

CONDITION



The PCM monitors the state of the purge solenoid valve circuit output driver. The
test fails when the signal moves outside the minimum or maximum limit for the
commanded state.

2008 Mazda CX-9 Grand Touring

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

Microsoft

Sunday, November 15, 2009 10:08:37 AM

Page 204

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