oil light on 2004 Buick Park Avenue

When first cranked the oil light will come on and stay on for approx. 3 sec. then go off. It is the only light that does this. Is there a problem with the oil sensor or the oil pump?

Asked by for the 2004 Buick Park Avenue
usually the oil light will stay on until oil pressure builds and then the sensor will turn the light off
Thanks, I found out it was the sensor....