Maybe this will help, on a 1999 you open hood, depending on witch
light you are changing.
On the inside fender panel there is a lever you have to pull up,
there should be a lock button you have to push in, in order to pull lever up.
Then just pull on headlight and it should pop out.
Hope this helps.
changing the bulb
How replace right head light
the headlight assembly needs to come out in order to replace the bulb.
Yes , according to the 1998 Mercury Mountaineer Owner Guide : ( the headlight bulb is # 9007 )
drop the bumper and take the headlight housing out
You replace the bulb the same as a 1998, which is answered further down the page.
Replace headlight bulb only when blown.
the headlight assembly needs to come out in order to change the bulb ive had to do that to my 98 as well.
Passenger side go in from under the hood and find the socket. Remove it and replace the bulb. Drivers side is a different story. You have to remove the battery to get at the socket.
On older vehicles you replace the entire headlight. On the newer vehicles you just replace the bulb unless the headlight assembly is damaged.
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How do you replace a 1999 Ford Escort headlight bulb?"