In my 99 Cougar, the lights (head, tail, dash) flicker. I've had it
"diagnosed" (HA!) as the alternator which I had replaced. The battery
also has been replaced. The alternator seemed to correct the problem for
a couple of days then it returned.
A grounding problem is my own idea but have no idea where to look after
checking the alternator and battery connections. Any help is
appreciated.