My grandfathers Durango, I think around 2003 has an electrical problem. When the head lights are turned on they don't come on right away but instead after about 5 to 10 seconds they flash on along with the dome light then turn off. It continues this pattern on & off about every ten seconds. The vehical did sit for several weeks with a drained battery & has done this ever since. Anyone experienced this? Does something need re-setting? If its something simple I would like to try and save him some money. Thanks for any info.