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NHTSA — Exterior Lighting Problems


really awful
Crashes / Fires:
1 / 0
Injuries / Deaths:
2 / 0
Average Mileage:
76,965 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2004 Mercury Grand Marquis lights problems

lights problem

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2004 Mercury Grand Marquis Owner Comments (Page 6 of 8)

« Read the previous 20 complaints

problem #44

Dec 012011

Grand Marquis 8-cyl

  • Automatic transmission
  • miles


2004 Mercury Grand Marquis. Consumer writes in regards to failure of headlights the consumer stated the headlights would just randomly go out and come back on after a minute or two. The consumer was informed lighting control module needed to be replaced.

- Greenbelt, MD, USA

problem #43

Sep 062011

Grand Marquis

  • 103,000 miles
The contact owns a 2004 Mercury Grand Marquis. The contact stated that while driving, the headlights failed without warning. The contact took the vehicle to the dealer and the dealer could not locate a problem with the headlights. The contact replaced the light switch but that did not remedy the problem. The failure mileage was 103,000. The VIN was not available.

- Mannerville, NY, USA

problem #42

Jul 012011

Grand Marquis 8-cyl

  • 58,000 miles
The headlights failed during operation of the vehicle while in light rain at night in town. I did not notice the lights failed, on coming traffic flashed their lights to tell me my lights were off. Pulling over to the curb I wiggled the cabling under the dash and the lights came on, I then proceeded to move again and the light went off. After a few attempts of wiggling the cabling near the lem module the lights stayed on enough to return to my home. This has been an on going situation with the lights, and I have been on the internet to troubleshoot this fault in the Ford motor vehicles. That this problem has been reported with out a recall is appalling. The location of the failed unit most likely is the reason for service mechanic estimates of $700 to $1500 to replace this part. One only has to go on the internet and write the 2004 lighting problem and see the lem module has a un-going product failure.

- Oberlin, OH, USA

problem #41

Jun 012006

Grand Marquis 8-cyl

  • Automatic transmission
  • 60,000 miles


The contact owns a 2004 Mercury Grand Marquis. The contact stated that the headlights shut off without warning. The lights would continuously flicker on and off. In 2006 and 2009, the dealer replaced the lighting control module however, the failure recurred. The manufacturer was made aware of the failure but did not offer any assistance. The current mileage was 121,000 and the failure mileages was 60,000. Updated 01/05/12 updated 01/09/12

- Hampstead, NC, USA

problem #40

Feb 012009

Grand Marquis

  • 60,000 miles
The contact owns a 2004 Mercury Grand Marquis. The contact was driving 45 when the headlights illuminated on and off intermittently. The vehicle was taken to the dealer where they replaced the switches for the headlights. The manufacturer was not contacted and the failure persisted. The VIN was unavailable. The failure mileage was 60,000 and the current mileage was 80,000.

- North Fraklin, CT, USA

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problem #39

Oct 062011

Grand Marquis 8-cyl

  • 34,234 miles
My Mercury marquis is unsafe! both of my night-time headlights went out at the same time. All other lights work fine inside and out. The head-lights now only work if I hold the high-beam bar, however, they do not work if I let go of the control bar. I drive my vehicle very little, and mostly during the day; however, I do take 70 mph interstate highway trips returning at night. There is no fuse for the head lights or the light control module in either the fuse box above the brake pedal, or under the hood. Further investigation reveals that the head light fuse is inside the light control module which is located under the dash above the gas-pedal. Also, I've learned that even when this lcm unit is replace, that a new lcm unit can be defective also. Common sense dictates that something electrical is causing the fuse to blow in the unit. I believe this indicates a looming fire hazard about to happen. Overheating the electrical system from where" if I would elect to have the lcm unit modified with a larger interior fuse, I fear this is not a solution either. Ford needs to find the source of the problem that is blowing this fuse even in the new units. The installation at the dealership is $700 or above. The market price of the lcm unit is $90. Fords needs to recall and replace this lcm unit for an indefinite period; however, since they are making a bunch of money replacing them, and no one has gotten killed yet, will they" I fear replacing the unit this week, an the new one failing and me, suddenly with no headlights possibly running over a pedestrian, or crashing on the interstate and me or someone dying. This problem makes my Mercury absolutely unsafe !!! I want an indefinite recall of this unit, and for Ford to find and repair the cause of the unit failing.

- Destin, FL, USA

problem #38

Sep 232011

Grand Marquis

  • 124,000 miles


The contact owns a 2004 Mercury Grand Marquis. The contact stated that the headlights shut off without initiation and without warning on an intermittent basis. The dealer advised the contact to bring the vehicle in for diagnostic testing. The manufacturer had not been notified and the failure was not diagnosed or repaired. The approximate failure mileage was 124,000 and the current mileage was 125,000. The VIN was unavailable.

- Slinger, WI, USA

problem #37

May 012007

Grand Marquis

  • 30,000 miles
The headlight would not come on. This first happened 2007, vehicle was inspected and repaired. Under warranty headlight modular. This happened again June 2011. Headlight modular needs to be replace again.

- Eldersburg, MD, USA

problem #36

Aug 262011

Grand Marquis

  • 80,000 miles
The contact owns a 2004 Mercury Grand Marquis. The contact stated that the exterior headlights would fail intermittently. The dealer diagnosed that the computer module failed and would need to be replaced. The vehicle was in the process of being repaired. The manufacturer was not contacted. The failure and current mileage was 80,000.

- Dumas, TX, USA

problem #35

May 092008

Grand Marquis

  • 150,000 miles
The contact owns a 2004 Mercury Grand Marquis. The contact stated that while driving 30 mph at night, the headlights and the interior lights would suddenly malfunction and stop illuminating, increasing the risk of a crash. The vehicle was taken to an authorized dealer, where a diagnostic test indicated that the head light control module was faulty. The contact did not have the headlight control module replaced. The failure mileage was 150,000.

- Coffeville, AL, USA

problem #34

Jun 012010

Grand Marquis

  • 70,000 miles


The contact owns a 2004 Mercury Grand Marquis. The contact stated the vehicle headlights and windshield wiper failed. The vehicle was taken to the local mechanic who performed a diagnostic that located the failure at the headlight control modulator and the windshield wiper motor. The manufacturer was contact and but provided no assistance. The vehicle was not repaired. The failure mileage was 70,000 and the current mileage was 90,000.

- De Valls Bluff, AR, USA

problem #33

May 182011

Grand Marquis 8-cyl

  • 42 miles
Head light turn off while driving for no apparent reason, then cycle back on for a few minutes and then turn off again, this continues with out end.

- Euclid, OH, USA

problem #32

Nov 292010

Grand Marquis

  • 100,838 miles
All headlights quit without notice of any sort. After replacing bulbs and switches, I went directly to Ford. They charged almost $700 to replace the "processor lighting control", which the service clerk explained was likely the problem. Since Ford knew this was a problem, why did they not recall the vehicles having this problem. We could have had a very serious accident.

- Addison, ME, USA

problem #31

Jun 112011

Grand Marquis

  • 89,567 miles
Head lights on my 2004 Mercury Grand Marquis will not come on. Parking lights work and hi beams. Got pulled over by columbus oh police department because I was driving with hi beams on. This is the second time that this has happened.

- Columbus, OH, USA

problem #30

Jun 082011

Grand Marquis

  • 40,000 miles
2004 Mercury Grand Marquis headlight will not come on. Must hold high beam lever to use headlights and drive with one hand. I replaced the light assembly didn't help.

- Baltimore, MD, USA

problem #29

May 052011

Grand Marquis 8-cyl

  • 92,350 miles
When driving at night the low beam headlights go out while vehicle is in motion. This failure is unpredictable and leaves the driver literally "in the dark" with the vehicle moving at whatever speed and direction it is going at. This is definitely a serious safety issue as my research has found that this is a common failure of the vehicle's "light control module" (lcm). Further research reveals that the Ford / Mercury automotive dealerships maintain a ready stock of this part for replacement at the hefty average price of $ $700. Given the severity of this safety issue it is difficult to understand why there has been no apparent action by NHTSA to require a recall by the manufacturer. This failure recurs frequently and unpredictably.

- West Cape May, NJ, USA

problem #28

Jun 202009

Grand Marquis

  • 50,000 miles
Vehicle has defective lighting control module (lcm). Headlights would not turn on until lcm was kicked. (lcm is mounted directly above gas pedal) now headlights are turning off while driving. (but come back on if the lcm is kicked. ) looking at ebay there are many companies that offer a total upgrade of your existing lcm. They install heavier duty relays. The part # on my lcm is 4W7T-13C788-aa. So it is evident that there is a problem with many lcm's in and around that model year.

- Dover, PA, USA

problem #27

Apr 272011

Grand Marquis

  • miles
The nighttime head lights failed on the Mercury marquis. 2004 model; we brought the car into the dealership to have the module replaced which is expensive.

- Mandeville, LA, USA

problem #26

Apr 142011

Grand Marquis 8-cyl

  • 86,000 miles
My 2004 Mercury Grand Marquis headlights keep turning off without warning at night. I almost killed a pedestrian as the lights went out at night and I couldn't see before stopping the car. I did however strike the empty babystroller they were pushing which contained groceries. I'm told by the dealer that it is a module. Costing $500. Plus $99 an hour to diagnose ( which will of course be a min of two hours ) ad then the labor for total of about $1,000. This seems to happen more often the not. I've looked online and found lots of people with the same problem. Fortunately there have been no injuries or deaths yet as a result that I'm aware of. So when there is a death because of this, whose is going to tell the family that this was aproblem that could have been avoided or fixed. We should have to wait for injury or death for action to be taken. The dealer ( Lincoln Mercury) says its a defective part ( module). This is a safety issue since you can't legally drive a car @ night without lights. Please look into this and make something happen, please !

- North Haven , CT, USA

problem #25

Mar 022011

Grand Marquis 8-cyl

  • 72,000 miles
2004 Mercury Grand Marquis outside lights goes off and on intermittently. I have 72,000 miles on my car. It suddenly happen one day while I was driving at night from my second job on the highway. It scared me nearly to death and is very dangerous.

- Euclid, OH, USA

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