Did you try jiggling the rheostat a little when it happens? Our 300M has been doing this for years at random intervals. It really needs a new headlight switch/rheostat. I figure either there's a little dirt or a little corrosion in there.
Probably should replace it. The one in my wife's Escort started to smoke at 30,000 miles. The 300M's well over 100.
Probably should replace it. The one in my wife's Escort started to smoke at 30,000 miles. The 300M's well over 100.