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No, GM has not used a fuel pump kill switch like other makes. The fuel pump relay is controlled by the PCM. If pump fuse ok. relay ok, then you could very well have a failed PCM with bad internal fuel pump driver. Here is the circuit
car would not fire, would turn. Mechanic sprayed starter fluid into air intake and car started for a few seconds. mechanic diagnosed as fuel pump. replaced fuel pump. engine ran that day and the next . then stalled again and acted as before. Mechanic checked power supply to pump and found that there is no electric current reaching fuel pump. check pump with battery. works fine.
I would triple check the fuel pump fuse, maybe get another relay. Lets hope the pump did not backfeed the PCM and damage it. I am thinking relay or fuse