Sometimes they come on, other times no. Sometimes they just go out while driving.
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2003 Mercury Grand Marquis Question: Where is the headlight sensor located on 2003 mercury grand marquis?
Answer #1pushrod March 13, 2013, 18:16Master
Try turning on the manual switch to see if that helps.
Replyjimdot, May 18, 2013, 07:54Rookie
sometimes yes and sometimes no
Replypushrod, May 18, 2013, 08:00Master
Go out on dim/bright or either way? If either way i suspect headlight switch, if only one or the other i suspect dimmer switch.