All of a sudden, headlights on my Mountaineer will turn off while driving at night, or they might turn on during the day. Problem is very intermittent.
Did anyone have similar issue?

 

seen the same on a 92 crown vic. needed the light switch to be replaced because it had the auto-reset circuit breaker built into the switch module. Check your owners manual to see if it says what circuit breakers you have (usually in the fuse box under the dash but may be in the box under the hood depending on year model if it's not in the switch). If you have a replaceable circuit breaker, you'll need to replace that. That will fix the cutting out.

it could also be the light sensor on the dash (which is usually a bugger to get to on newer vehicles). if you disable the automatic lights and use them manually does the problem persist? If not, it's the sensor. if it continues, it's probably the circuit breaker and/or the switch.

also, what year is your Mountaineer. That will help us determine which problems may actually be happening. There may be some other issues I haven't thought of as well.

 

Car is 2000 model...

 

do you have automatic lights? (I'm not real up to speed on standard options on the mountaineers)

did you try disabling the automatic lights?

if so, did the problem persist?