2000 Chevy Suburban will not start no fuel at fuel rail, fu

Good morning
thank you for your help.
Yes we checked the fuel press, nothing at the
schrader valve. I now dropped the tank again
and checked voltage at the connectors, pump
and sender unit both have 0 volts. Removed the top
half of the fuel/relay box and checked connections
and for signs of coarosion all look good. I did see
next to the fuel pump relay a small recpt marked
Prime. Will the aid in trouble shooting. Next
I will pull the relay and run batt voltage through
the grey wire and check voltage at the pump
connector so I can rule out a damaged or burned
wire. I have questions re: the security system
is it possible that I am in some type of anti theft mode dissabling the fuel pump.
Thank you again for your help.
If you have any idea what I should check next
please reply
thank you Lori