A little more info on the headlight problem on the 2003 Marquis. The headlights work most of the time, When I first start the car after long periods of sitting they work. If I turn off the car and and return and restart the car after approx. 10 minutes the parking lights work but headlight don't. If I put on highbeams and hold in place the Headlights work (only highbeams)???

SOURCE: 2003 Grand Marquis Headlights

New Light control moduel solved problem

Ned C Cook

• 3433 Answers
• Posted on May 13, 2009

SOURCE: headlights work but dash lights and parking lights are dead

dash and tail sre tied together, so chk tail light fuse.

SOURCE: Headlights work intermitently

HI,Inspect the #27 fuse holder of the Central Junction Box (CJB) for a questionable contact issue with the male spade of the fuse, which may cause intermittent loss of contact.if ok sounds like you need lcm= light control module.

SOURCE: 2003 mercury grand marquis headlights will cut out

My 2003 Mercury Grand Marquis has the same problem. We found out it was the headlight module located under the dash above the gas pedal. The black box has wire connectors coming out of the back. Hitting the box worked for a little while, then I had to reach in the back and wiggle the wire harness. The dealership wants 500.00 to replace the unit. I consider Highway Robbery! They have installed a faulty piece of equipment on my Luxury car that could easily be life threatening but we know it won't be recalled until someone dies because of it. My husband was able to remove the unit and looked it over it had two circuit boards and he was unable to visibly see any problem or loose wire. He cleaned the connectors and used some electrical terminal grease on the wires, this improved it for a short time. The problem still exsists. I have sat for 30 minutes or more waiting for them to go through the On/Off cycle till they stay on for the 45 minute ride home from work. I have beat the box with my flashlight (maglights handle the abuse, my fingers and nails don't) till it came loose from the brackets that hold it. I leave my car running while pumping gas, short shopping trips and start it 20 or 30 minutes early before leaving for work. It is frustrating and dangerous. If this is the kind of quality in our American made cars it's no wonder they needed a BailOut! The only thing we have found to "fix" it is to find a used part that could possibly have the same problem shortly down the road or pay the theives at the dealership to replace it.

SOURCE: 2003 Grand Marquis Headlights

the recommendation above is strongly sound well but, before psending big amount of money to replace the lighting controller it is better to check the wiring connection of the existing one since i had the same problem, and after i aligned the connection wires, lights became healthy and functioned well.

Abdulatif R Talalawah