This applies to 2008 Nissan Maxima, Quest, Pathfinder, Frontier and Xterra, and all 2009 models. On-board DTC P0456 for the applied vehicles is sometimes performed when the engine is not running. This is known as Engine Off Natural Vacuum (EONV) diagnosis.
The following freeze frame data is normal when DTC P0456 is stored during EONV diagnosis:
CAL/LD VALUE…………….….0%
COOLANT TEMP…………….-40 Deg F
L-FUEL TRM-B1………………100%
L-FUEL TRM-B2………………100%
S-FUEL TRM-B1………………100%
S-FUEL TRM-B2………………100%
ENGINE SPEED………………..0 rpm
VEHICLE SPEED………………0 mph
INT MANI PRES……………...….0 psi
ABSOL TH-P/S……………..……0.00%
B/FUEL SCHDL……………..…..0.0 msec
INT/S TEMP SE………………..-56 Deg F
FUEL SYS-B1………………..…..Mode5
FUEL SYS-B2………………..…..Mode5
COMBUST CONDITION……..…Mode1