There's a gangway that plugs into the top of the headlight switch; for some reason one cell tends to burn up in older Towncars. If you haven't noticed, your running tail lights will also be out. You can replace the part (not the whole headlight switch; just the gangway), but it will likely keep burning out. You have to take the dash trim off to get to it. It's a bit complicated, but better than the $350 or so a shop will charge you, and that's not even a permanant fix as it's just a symptom of a deeper electrical problem (one that will cost more to fix than the car is likely worth). You can get the part at a junkyard for about $8 or new for $30. I've had a used one last for six months and a new one burn up in a day. Hope this helps.
burnt out lightbulb!
Bad ground to the dash.
there is a bad ground somewhere
If the headlights are not working correctly on a 1990 Corvette, the fuses or lights could be going out. Replace the old fuses and check that all wires connected to the lights are functioning correctly.
If you are talking about the dash lights , check your tail light fuse . they are on the same curcuit
A short to ground causes all fuses to blow. If you have a trailer connecter then start there first.
Check grounding wire's then use a test light
Taillights and daytime running lights not working may be caused by a blown fuse. The fuse can be found in the fuse box in the engine compartment.
My '93 Sport does the same thing periodically. This may be a cool safety feature Jeep uses to indicate your brake lights are not working. If this is the case it is as simple as replacing fuse or bulbs. if your lights flicker on and off i wouldheck for a short in your electricle systm or if they went out and stayed out i would start by checking the fuses in your fuse box.hope this helps.
short circuit , or the battey needs replacing it may not hold a charge
Where is the starter on a 1990 lincoln mark 7
1990 ford festiva dashboard light goes out when brake is applied and the instrutment guages some time don,t work what causes that