i have a 1993 mercury grand marques. The headlights are going off and on and n o back lights...solutions?

check the fuses?

I have the same problem and I checked all of the fuses and they are all fine if anyone can come up with anything please let me know

Its the headlight switch..I have replaced mine 3 times..and after about 6 months to a year they go out again...seems to be a common problem with this car...if you pull the switch about to halfway point headlights and tail lights will work and extend the time between changing switches...but this only works for a while..its some kind of electrical defect

Rufus is correct to a point. the main issue with this is the wiring is not shielded from moisture like its supposed to be. Over time the gasket they put in the location of these wires which is under the light control switch wears out an causes a basic electrical grounding error. Best way to fix this is take it to your local car guy who can do a simple rewiring of the unit. Mine actually shorted out an stopped working all together after 105000 miles on the car. ( Thankfully a garage kept car most of its life ) might happen quicker if your car sits out or is rusted like alot of the models from mid 90's.

I also have a '93 Grand Marquis LS with digital instruments, and have the identical problem that Rufus had. Where is this gasket that Mark speaks of? I also have a slightly burnt connector on the plug that goes to the headlight switch.