Headlights do not work?

As I was driving at night I realized that the main headlights do not turn on. Seems like they both went out at the same time. When I turn lights on everything turns on except
for the main two. Checked fuses all over and everything looks good. What could be the problem? Thanks

I have bright lights but no regular head lights, already replaced the multi functioal dimer switch, but still no lights, checked the fuses they are good.

Silly question, but have the lights been checked to make sure the low beams aren't burnt out? The headlight switch and dimmer switch/multifunction switch are about the only thing that can turn them on. Check the bulbs. If you can power them up then you have a light module or daytime running light module that has failed, the wiring doesn't usually fail to headlights. Good luck

When it get below 40 F (I am in Arizona) the headlights, high and low beam will not come on until the car is warmed up. I suspect it could be the headlight delay module but, I cannot find where it is located in the car.
All other running, turn and four way flashers work just fine not matter what the temperature is.

I have the vehicle listed above that has developed head light problems. At first it was only when the temperature was below 40 degrees Fahrenheit. I tried a lot of things. The multi-switch was replaced by my mechanic and it has worked great for at least a couple of years. I replaced the headlights (I knew that was not the problem) checked connections, and found nothing wrong. The headlights would not work but all other lights did. One morning I got up and the battery was stone cold dead. That was very odd because the battery was not that old. Charged the battery and the next morning dead battery. The charging system was working fine, I went to the place where I got the battery and they replaced it free of charge. Drove it two miles home parked it and the next morning dead battery. I found a dead short between positive and negative cables on the battery with the positive cable removed from the battery. I started pulling fuses and the short did not go away. So I was advised to do a "drain test" on the system. So I connected an ammeter to the positive cable and the other end to the positive post and made sure nothing was on like interior lights. I started pulling fuses because I saw 3 amps draining the battery with nothing on. It turned out to be the dome light in the passenger cab and the cargo area dome light. Disconnected the lights and saw maybe a trickle current of around 500 milliamps which is normal. That solved that problem and I thought maybe it would solve the headlight issue. Well it's not 40 degrees here anymore so the lights worked every time I tried them. I loaned my son the car and warned him about the lights. Sure enough he was out late at night went to drive home and no headlights. There is no relay in the circuit so it's not that, I am at my wit's end. The only thing in the circuit I have not been able to check is the headlight delay module and it's connections. But I can't any information anywhere about where that module is located. Does anybody have any information on that module or this problem? BTW, when the lights work I cannot make them quit. I have tried freeze spray to duplicate the temperature and they work just fine.

Roy, I don't know what "BCM" means and the first two schematics show a headlight relay. This car does not have a headlight relay in it. This is a 1998 Cherokee.

Roy,
None of the previous schematics I have seen show a headlight relay. The one in your schematics designates it as an "automatic headlight relay". This car does not have automatic headlights, it has the headlight delay module for keeping the headlights on after the ignition switch is shut off and that works fine. I turned the lights on and I pulled the three large relays in that kick panel and none of them affected how the headlights work. There are four circuit breakers but, according to my documentation those are for power seats, power windows, the alarm system and the rear window heater. I haven't found anything on the large relays.

How can I not have power to the dimmer switch if the lights are working? What about the relay in the schematics you provided? I have a Chilton's and it is sorely lacking in the schematics but, again nowhere did I find a reference for "an automatic headlight relay". All of the other lights work just fine including the dash lights when this occurs. Running, fog, blinkers, fourway, interior,
side lights tail lights all function it is just the headlights that will not work when the car is cold or at night when it's been shutoff for a while. My son drove it home with the light switch on the entire time and no headlights, but all other lights were working, The next morning I tried the lights and they worked fine. They do not work on high or low beams when this happens.

Roy,
High and low beams do switch when the lights are working.
I will attempt to check voltage at the dimmer switch when the lights are not working, but, it is difficult because I am not sure when they are not going to work. When the temperature is around 40 Fahrenheit they fail, but now that it's May in Arizona that's not going to happen for a while. However when it failed the last time it was not cold and the car had been sitting for a while.

Hello, I have the vehicle listed above Sport. On my way home from work my headlights went out on me. My running lights and dash lights still work. It can't be the fuse because about 20 minutes after they went out they came back on for another 15 minutes before going back out. What could this be? Scariest drive of my life since I live in the mountains.

Roy,
How do I check power to the dimmer switch while it's running? To even get to that switch I had to remove the negative cable form the battery, and then it took quite a while to get the switch out so that's almost an impossible task to do on short notice. However, I did pull and replace the switch so far no failures.