dash lights and panel lights on 1990 Cadillac Fleetwood

when I back out into the daylight my dash goes very dim
and also when I durn on my head lights
how can i keep my dash lights bright

Asked by for the 1990 Cadillac Fleetwood
well I need an answer but I can not figure out why all of a sudden these lights go very dim when they get out into the light and very dim when I drive with my lights on at night