I have a 99 Nissan Sentra. When I first bought the car, it had the keyless entry remote. Not too long ago, the remote stopped working. Just the other day, the hazard lights began to flash randomly by itself as if I where unlocking/locking the doors. I was told to change the battery or the remote might be dirty, but I don't have the remote. The doors do not lock/unlock but the lights flash as if I was pressing the button on the remote. Any ideas what might be causing this? Any advice would be appreciated.