when I started my car there was a loud beeping sound that lasted about 20 seconds. The same exact thing happened the next time I started the engine about an hour later. There aren't any warning li

My mother had this happen and she accidentally opened the hood and the car beeped at her till I opened the hood and didn’t find anything but she told me the next day the issue stopped so pull ur hood latch and close it firmly also check gas cap if not tight or door not closed honestly I don’t know what else it could be without pulling the codes to see what sensor is signaling the noise hope this helps