I am new to the site and looking for some help please. My 2005 F-150 King Ranch is having a little trouble. My headlights stopped working on autolamp setting but the parking lights come on. It did this a while back and I started using the manual setting. For some reason, they starting working again and have worked for months. It started again this evening...parking lights come on, but headlamps don't with the auto setting. Can anyone please give me any reason this happens? I haven't done anything diifferent than normal that would cause this...that I know. I have read a few threads but haven't seen any real solution yet. Thanks for any help.

 

Maybe a loose connection on the relay harness or maybe a goofed up relay id start there

 

The sensor on the dash may be bad and not completing the circuit when it gets dark.

 

^^x3. That sensor is tied in with the automatic A/C temp control too. Sometimes called a "sunload sensor".