head light problem
Check the fuses. If they all good check for power into and out of the headlamp switch.
If fuses ok an checking the power into an out of the switch dosn't work also check the wire harness located under the panel the knob is attached to. Being that its a 10 year old car now you may have a bad wire in there from all the years of use. Easy fix if you know how to get to it ;)
If the high and low beams do not come on, yet the lights do energize when you hold the "flash to pass" lever towards you, then it probably is the LCM (Light Control Module.) And there is now VERY GOOD NEWS!!! Ford just started fixing them for FREE!!! (Ref: Ford Customer Satisfaction Program 14N01) Ford/Lincoln/Mercury has finally decided to deal with the rat-nasty LCM's they have been putting out. I just got the letter on this from Ford last week. Without starting a safety recall, (as they should,) they are extending the warranty on the LCM (based upon VIN number,) to 15 years or 250,000 miles whichever comes first. AND if you paid earlier for this replacement and have the receipt, they will REIMBURSE you for the repair provided it was done before the notice came out. The window to be reimbursed for an earlier repair looks to be between April 1st, 2014 to October 31st, 2014. This window also applies if your car is under 15 years, yet has exceeded 250,000 miles. Ford's LCM replacement is completely without charge for parts and labor. Retail owners should have their VIN number handy and call the local Ford/Lincoln/Mercury dealership for an appointment. They say it should take a half a day yet could be longer due to dealer "service scheduling requirements." They will only replace LCM's that do not work, but mine lasted 10 years before it started acting up. This gives Ford a way to show concern, without really dealing with the 1000's of LCM's that will fail after this window closes in the future. Ford only "invented" their LCM after their service departments were losing money on a system that smaller repair shops could easily fix. Nice to have a little black box that they could unplug and swap out so they could charge $800-$1000 in parts and labor then repair at the factory with three $10 relays. Anyway if you have any questions about this "un- recall" you may contact the Ford Customer Relationship (I'm in a "relationship?") Center at 1 (866) 436-7332 either they or the dealer can tell if your vehicle is covered if you have the VIN number handy. IN THE MEANTIME. Should you need to get granny to the hospital at night, you can try this AT YOUR OWN RISK. The LCM on my 2003 is located about 18" directly above the gas pedal under the back of the dash... Turn on the lights and give the LCM a tap with your foot. This will often engage the cheap Ford relays and the lights will come on. But you should make that appointment with the dealer before everybody starts fighting for access to the same part. I also don't know if Ford would be willing to call someone a liar if he claimed his headlights stopped working because he thought it is just a matter of time before the lousy relays in his LCM failed, since this is intermittent, and asked for an LCM replacement under this warranty as well. That is why this should be a RECALL, and not just some bean- counter's way of slithering out from all of the angry customers that demand action today. My Grand Marquis is really a fantastic car, but having to drive 50 miles home on narrow country roads with one terrified hand while holding the "flash to pass" arm with the other, and risking my life because Ford played it cheap with some relays on their flagship chassis for a decade or more, really makes you wonder what they were thinking.Remember: you have to take your car to a DEALERSHIP to get this fixed for free under warranty. DO NOT TAKE IT TO A PRIVATE REPAIR SHOP unless you just want to throw your money away!
Can you post a pic's for the Light Control Module, and the location on the car please.
Looking for a Used Grand Marquis in your area?
CarGurus has 1,837 nationwide Grand Marquis listings starting at $1,600.
Search Mercury Grand Marquis Questions
Mercury Grand Marquis Experts