Fuel pump problem

I have a 97 cadillac sls and my fuel pump is not coming on so first I checked the fuses all okay then checked the relay its was good so thinking it may be the key so went to dealership my friend told me lock cylinders go out due to the getting cut so I checked that out and found a bare spot on lock cylinder wires so I replaced the whole cylinder and key still nothing so I thought it had to be the pump so I pulled the tank checkd wires had power and ground so pulled the pump out and tested it works just fine dont know what to think other than anti-thief module cause even dont work but when it wants to