Can't turn off headlights

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Russbo

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Headlights (appear to be low beam) remain ON despite headlight switch in OFF position. (Other positions work ,e.g., fog lights.) High beam indicator illuminated. Flicking high beam or trying to turn them off has no effect. Automatic shut-off occurs after 10 minutes or so. But open door or put key in ignition switch starts the cycle all over again. Suspect headlight switch OFF contact has failed. To check it I have to remove panel its mounted to. Am reluctant to force plastic panel. How do I remove it? Yes, I know that disconnecting battery shuts lights off but it starts all over again as soon as battery is reconnected.
 
So, if you turn it to parking lights, do the headlights go off?
I assume you have the same problem with the auto setting as the off setting? If so, then a problem with a single contact in the switch is unlikely.

The switch is behind the trim panel, not mounted to it.
You will need to remove the lower trim panel (under the steering wheel) first.
http://deneau.info/ls/s6x~us~en~file=s6xh1020.htm~gen~ref.htm

Troubleshooting for your problem:
http://deneau.info/ls/s6x~us~en~file=s6xh1003.htm~gen~ref.htm#PS2-E

(You didn't give a year or even a generation, so I assumed gen II...)

If there is no warning chime when you open the door (key out, light switch off or auto, headlights shinning anyway), then the problem is more likely to be in the FEM.
 
This couldn't be a DRL programming issue could it? I heard it was an option on all LS's or maybe Canadian LS's?
 
No, DRLs are tied to the key position. The FEM basically says "key on, always turn on headlights regardless of switch". This is more like the switch is telling the FEM that the headlights are requested On all the time.

My bet is the headlight control unit is faulty. They can be acquired from junk yards fairly easily.

Follow what Joe said. The lower panel is easy and you can't really break it. The trim panel around the headlight is pretty stout, so you should be fine. Use a metal trim removal tool (looks like a small spatula) and pry from the lower edge that is exposed when the lower trim is removed. The plastic scraper style might break before the clips let go of the trim.
 
Tks to all for the comments about my headlight problem. Thought it might be an 'infant mortality' failure in the clockspring as I replaced it about a month ago to successfully repair an inop cruise control. Have since eliminted any contribution from clockspring. BUT I found that when disconnected the cable to the Turn Signal stalk-mounted assembly, the lights go off. From one wiring diagram for an '02 it shows the "Flick-to-Pass" feature is always hot and is directly connected to the high beam headlights. Ig this switch is stuck in the 'closed' position the high beams will go on, regardless of any other headlight, parking or fog light operation. However, another wiring source shows that this same switch controlled a headlight relay in 2000 and 2001 LS. Appears it was removed for the simpler operation (and to save the cost of the relay and wiring beginning with 02. My LS was built in 8/02. Can anyone confirm this and if there really is a headlight relay, where is it located?
 
The clockspring has no involvement with the headlights at all.

The high beam and flash-to-pass switches were never connected directly to the high beams! Your diagrams are wrong, or you are reading them wrong. Those two switches along with the headlight switch and the light sensors connect to (are read by) the cluster. The cluster then communicates with the FEM to tell it what lights to turn on. Flash-to-pass is honored anytime that the car is awake. They never used external relays, that would have made DRLs using the high-beams rather difficult.

Headlight relays(transistors actually) are in the FEM. The gen II /with HIDs does have an external low-beam relay. Also, both generations do have an external fog light relay.

If your multi-function switch is bad, then the solution is to replace it.
 
Tks all for the responses, especially joegr. My 2002 LS V8 was made in 8/02 and doesn't have DRL. My headlight (HL) wiring diagram came from a specific 2002-yr Google search and AIR was linked to this website. I trust its validity and I learned though extensive web searching that HL relays were in fact used prior to 2002 and then went to simple switching to control the HLs. FWIW I am a retired electronic engineer and can read schematics and wiring diagrams :). Also, FWIW the ignition key is not inserted (KOEO) and the only 12v power to this area is via the Engine Compartment Fuse Box (hot at all times). What puzzles me is that if the multifunction switch connector associated with the clockspring assy is disconnected, the high beam lights go off. (Also when the battery is disconnected.) If the battery is reconnected, the high beam HLs are off. But reconnect the multifunction switch and the lights go on. Checking continuity of this switch failed to show any pass through electrical paths. And activating the high beam flash-to-switch or dimmer switch doesn't provide any continuity, suggesting the switch is open and bad. But an open circuit would not provide any electrical path through - -- no harm done. About the only way the high beam could be turned on is via the automatic headlamps/delayed exit bus. That circuit will turn on the high beam indicator and both high beam HLs. But the automatic HL delayed exit appears to work as advertised because leaving everything connected results in the HLs going off after a 10-minute or so delay. How that happens, I don't know. Maybe there is a 'sneak circuit' activated when other connections in the multifunction switch (or a failed component in it) are made. Another interesting observation: reconnecting the battery and not the multifunction switch connector, the panel-mounted HL switch works perfectly, thus seemingly eliminating it as a remote source of this problem. (My 3rd printing July 2002 Owner Guide says this will happen - - auto HL turn-off - - if one forgets to turn off the HLs.)
I don't have a schematic of the Front Electronic Module (FEM), but I'm beginning to suspect a fault in it since many lighting functions are controlled by it. I disparage the buying a replacement FEM in the blind but I'm beginning to believe the root cause of this peculiar failure is in it.
Anyone out there have any thoughts?
 
I am an active electrical engineer. I thought you wanted help with this, not to argue something that you don't seem to understand.

Your 2002 LS V8 has DRL capability. It's just a programming setting that turns it on or off. The hardware is the same for the US or Canada. On the ones going to Canada, they turn DRLs on, on the ones staying in the US, they don't. If you move to Canada and take your LS, then a Canadian dealer will (for a fee) hook up their scan tool and turn DRLs on for you.

You are just wrong about the schematic. I get mine from Helm Inc., they published the diagrams for the Ford dealers.

The cluster and FEM have power when the car is awake. The ten minute timeout is not the "delayed exit." The headlight turn off delay is settable from the message center. It's range is from 30 seconds to 3 minutes, if I recall correctly. The "10-minutes" you are talking about is when the car goes to sleep after the last activity.

The flash-to-pass switch and the high-beam switch are connected to resistors inside the multi-function switch assembly that connect to one signal wire. The cluster reads the resistance on this signal to determine what it needs to do.

I tried to help. I am done. Perhaps someone else will chime in.
 
joegr, I didn't intend to insult or argue with you. Quite the contrary, you have really provided a well-appreciated help and keen insight about info I am not privy to. From what you have just posted we have an apples and oranges situation in that there are two vastly different wiring diagrams associated with the high beam operation. I really think I understand my problem based on what info I have on hand. If you are interested, Google '2002 lincoln ls high beam wiring diagram' to see the wiring diagram I have been referring to. FWIW I now have the Ford 2002 Lincoln shop repair manual DVD on on order and I hope it will provide what additional info I need. (Maybe it will clarify the issue :) ). I know nothing about the Helm's schematic or wiring diagram; wish I had access to it. My Owner's Guide states the DRL is an option and my purchase documentation does not show any exercising (or declining) of this option. If this is a programming exercise, whether it is operable is a moot point since it, AFAIK, is currently disabled in my LS. The existence of resistors inside the multifunction switch is news to me. I checked the multifunction switch connector terminals several ways and found no continuity in any combination of paired terminals. Checked originally with Low ohms and a buzzer function. Then checked with High megohms. Thinking there might be a polarized component inside, I reversed the ohmmeter connection and got the same result. Later I took the multifunction switch apart, didn't see any resistors or electronic components inside. Maybe I overlooked something.
You cited the FEM having power when the car is awake. I'm not certain what 'awake' covers but all troubleshooting I have described took place with KOEO so no power s applied anywhere other than where 12v. buses are "hot' all the time. So, the FEM is sorta out of the circuit, unless it is actually powered in this scenario.
 
FEM has power all the time.
Post the link to the diagram you are talking about. When I tried that search, it returned a diagram for a Lincoln Town car, which did have relays.

Pin 8 is the common to the multi-function switch. It is grounded by the cluster. Pin 5 is the high-beam/flash-to-pass signal. It is open when the switch is in the neutral position. It is connected to pin 7 via a 330 ohm resistor in the flash position, or to pin 7 via a 2.2K ohm resistor in the high-beam toggle position. Note that a DTC is stored in the cluster if it reads a resistance that is way off from 15 or 60.
The turn signal part of the switch is similar (no direct connections to any bulbs), using resistors as well. Note that the hazard function works anytime and involves the cluster, FEM, and REM. All of these modules have power all the time. They get a switched power signal to tell them what mode the car is in. The REM controls all the switched power feeds for the car, and it will keep it all awake if the hazards are on.

This is not the official Ford diagram, but it has the advantage of being simplified down to one page.
gen1-headlights.jpg
 
Okay, no edit function, I guess.
Corrections : Pin 8 should be Pin 5. Pin 5 should be Pin 7. And then the last two mentions of pin 7 should say pin 5. (I mixed the generations a bit.)
 
joegr, Again, tks for your input. The Google link to the wiring diagram I was referring to is: 2002 lincoln ls high beam wiring diagram. That leads to a screen with a whole lot of pix and diagrams. In the upper left corner of this screen is a wiring diagram (that's almost readable). Click on this image and the next screen is the wiring diagram I have been referring to.
The wiring diagram you posted is quite different. Regrettably the resolution is poor and that precludes reading any of the diagram printing. I tried to enlarge it with zero success. Also printed it; same result. Tried reading from screen using magnifying glass. The characters simply fall apart when expanded. But it appears that the lower left corner shows the multifunction switch portion that controls the flash-to-pass and and the high beam ON along with the two resistors you cited. In the upper right corner is the headlight relay that is activated by a signal (ground perhaps) in what I think is the FEM. (I can make out enough letters to identify it.) If there is a fault in the FEM and it is hot all the time, that could result in the high beams being lit. If so, pulling that relay should extinguish the high beam lights. I don't know where this relay is but yesterday, with the high beam lights on I pulled every relay in the engine compartment 'fuse box' and did the same to the trunk located fuse box. None turned off the lights, unless I accidentally skipped one. Maybe this relay is in a different location.
Next opportunity I have will be to dissemble the multifunction switch and look for the piece part components you cited.
Aint working on cars fun :)? Don't know how anyone can repair current production autos without a sophisticated, computer controlled test device.
 
Sorry, still wrong. The relay in the upper right corner is the fog light relay. I already said that was the only relay. The headlights are driven by transistors in the FEM. I don't know why that is so unbelievable to you.
The FEM is the box on the upper left. The cluster is the box on the lower right. Once again (maybe the last time?) the cluster reads the inputs (switches and light level sensor) and commands the FEM and REM as to which lights to turn on and when.

How have you narrowed this down to being the FEM as opposed to the cluster or the multi-function switch?

The upper left is for a Lincoln Aviator, not an LS. Why not just click on what you are talking about, copy the address from the address bar, and then paste that into your post? That way there would be no doubt that we were both looking at the same incorrect diagram.

The image I uploaded was in high enough resolution to read. This site compresses them. I don't know how to get around that.
 
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