DTC P0451 [MZI-3.7]
DTC P0451 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES
DIAGNOSTIC PROCEDURE
DTC P0451 (MZI-3.7) DIAGNOSTIC PROCEDURE
DTC P0451
Fuel tank pressure sensor range/performance
DETECTION
CONDITION
z
The fuel tank pressure changes more than 14 inches of water in 0.10 s. Fuel tank
pressure sensor output is offset by + /-1.7 inches of water.
NOTE:
z
For some vehicle applications, DTC P0451 is set for a fuel tank pressure
sensor range (offset) concern. The DTC P0454 replaces the original P0451
for intermittent (noisy) sensor concerns. Until the phase in process is
complete, noisy or offset fuel tank pressure sensor concerns may set DTC
P0451.
POSSIBLE
CAUSE
z
Intermittent open or short in the fuel tank pressure sensor or the fuel tank
pressure sensor signal
z
Fuel tank pressure sensor malfunction
z
Connector or terminal malfunction
z
PCM malfunction
STEP
INSPECTION
ACTION
1
VERIFY FREEZE FRAME DATA
HAS BEEN RECORDED
z
Has the 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
z
Verify related Service Bulletins
and/or on-line repair information
availability.
z
Is any related repair information
available?
Yes
Perform the repair or diagnosis according to the
available repair information.
z
If the vehicle is not repaired, go to the next
step.
No
Go to the next step.
3
VERIFY RELATED PENDING CODE
OR STORED DTCs
z
Turn the ignition switch off then to
the ON position (Engine off).
z
Verify related pending code or
stored DTCs.
Yes
Go to the appropriate DTC troubleshooting. (See
DTC TABLE [MZI-3.7]
.)
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 10:08:38 AM
Page 212
© 2005 Mitchell Repair Information Company, LLC.
