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Help! My Headlights Wont Go Off!!

09-22-2004, 08:54 AM
My headlamps are staying on all the time. It's only the headlamps, no markers or tails. Turn on the switch, the other lights come on. Shut switch off, all go out but the headlamps.
I have tapped on all the relays under the relay panel, no help.
Was going to try to do a new h/l switch, but I gues I'm too stupid to figure out how to get the door panel off.
Any help would be great, my wife hates to disconnect the battery to drive HER car!!

09-23-2004, 06:23 PM
Hi, welcome to the forum.
You didn't say what year your car is but the newer models have "Always on" headlight systems for daylight safety driving and unless you fudge around with the dash controls you can't get them to normally go off until after you stop (or pull off the highway and put the tranny in PARK).

Do they stay on for a little while after you turn the car off, take out the key and get out? If so they are probably doing their thing correctly!

09-24-2004, 12:50 PM
My car is a 1994 and it isn't equipped with daytime running lamps.
The crazy things will stay on until the battery dies if I dont disconnect it.
It sure acts like a relay is sticking, but I have beat on everyone in the relay panel and nothing, they stay on. The really crazy thing is, it's just the headlights themself, no tails or park lamps.
I have purchased a new switch (cant hurt if it doesnt fix it) but I havent figured out how to remove the doggone door panel!
Any suggestions???

02-15-2005, 05:17 PM

I am replying to you about the Headlight problem on your 1994 Lesabre. I am having the exact same problem right now and I am wondering how you fixed the problem on yours.



auto trainy
02-18-2005, 06:02 PM
When you reconnect the battery do they come back on?if they do then it could be the relay has welded contacts and beating on it won't help.It also could mean that there is another signal telling the relay to stay on or a short in the wiring for the headlights.I just looked at my 95 manual and they mention a Lamp Control Module that which could be your culprit
but the location of it I cant help with,good luck.

02-28-2005, 07:52 PM
If only your headlights are on, but not your taillights, then your headlight control switch (in the door) cannot be to blame. Why? Because it sends a signal (off or on) to the Light Control Module (LCM) when you turn it on, which then sends the signal to your headlights AND taillights AND park lights to come on. Meaning the door headlight switch does not send a separate signal for the headlights and the taillights, but rather an on or off for either the headlights AND taillights, or an on and off for either the park lights AND taillights. The signal to those is controlled by the LCM mentioned above. If your LCM is sending out the proper signals your other option is a wiring short (the short would have to be to a power source, which is highly unlikely). Where is your LCM located? It is the brown or black plastic box directly above your fuse box and connected to the same plastic bracket that also holds your fuse box. How do you get the LCM out? It is not super easy, but you slide it about a half inch (down I think), then pull it away towards the front of the car. It has two connectors hooked to it. One is smaller, and one is larger. The larger one has a 7mm bolt helping to secure it to the LCM. I had to replace my LCM recently, which was bad. However, the salvage yard was totally unfamiliar with the part, which they said indicated the parts are generally bullet-proof (they rarely fail). Nevertheless my car would turn it's head or park lights on and off spontaneously with the key off--killing my battery within a day or two. The salvage yard sold it to me for $50. Much better than the $177 the Buick dealership wanted.

To test whether it is your LCM or not, do the following: remove both connectors to the LCM after you remove it (if you can). Take the connector with the 7mm bolt connected to and and run a jumper wire from a known 12V source (somewhere on the fuse box will be an active wire with 12V--connect a jumper to it--or the red wire in the connector in question I think is 12V at all times), and touch it to yellow to check headlight operation, and brown to check park light operation (I believe these are the correct colors--it won't hurt to touch the orange just to be sure in case the others don't do what you expect). These two wires are the wires that will engage the headlights or the park lights if a 12V source is presented to them, but I can't remember which two are the ones 100% (but it is not the black/white ones, or the fat pink one). When (or if) you find that touching the jumper causes the headlight/park lights to light, , then you will know that the wiring from the LCM connector to the lights are okay. If the lights are on with out the LCM being connected, then you have a wiring short to a power source (very unlikely). If you find that the wiring is okay through the above test, you need to replace the LCM.

PS. There is no headlight relay on this car, only a headlight switch, then a LCM, then wiring to the headlamps/taillamps.

Good luck.

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