4.8l sierra 2012 starts dies .

[Don Dilldine]

Truck starts up runs 10 sec dies won't start for awhile unless I take bat cable off then  tap cable put back on starts up then dies have to remove cable then fuel pump works if i dont do that fuel pump does not run getting no power to fuel pump fuse and will still run without it 

[CamGTP]

Is the security light on in the dash?

 

Do you have a spare key you can try?

 

If the truck has a fuel pump control module, it'll run with that one fuse pulled. You have to pull the relay for the FSCM/FPCM to stop the pump completely.