Dead Fuel Pump

By now i'm sure this is like beating a dead horse, but need some answers.
My 2000 Escalade isnt starting again. Replaced Pump just over a year ago, now having trouble again.
I have also had the ignition harness replaced due to previous owner slamming the tilt every time he got in and out of the truck and stretched the wires, frustrating me with anti theft issues.
The question is would the security system disable the pump on this year truck, as the older VATS systems did not pulse the injectors.
It seems that if the truck sits for a day or so it will eventually start.
ANY HELP IS GREATLY APPRECIATED!!!