Originally Posted by mleindek
Assuming you didn't make any changes to your headlights/ electrical system I'm gonna start by the very obvious, check that the lever is actually in the AUTO mode lol.
That cleared I would start checking fuses (I don't think the sensor has a fuse for itself so something else might be not working if you have a blown fuse).
If fuses are ok I would check the connection with the sensor (it's in the dash on the passenger side near the windshield).
Did you try the good old battery disconnection for a while so sensors/ bcm resets?
Lastly I would change the sensor but I don't know if that's a piece that will fail, it can, but still...
Sorry I can't help you more, I'm fairly new to the truck and frankly I don't use the AUTO function at all... Hope you can solve it.
Thanks for the quick reply. No changes have been made to the headlights or electrical system. And yes the switch is in auto mode (I agree sometimes we overlook the most obvious). The rest of the cars lighting works in auto mode, if we place a pillow over the dash sensor all the exterior lights come on but the headlights turn off. Remove the pillow and the exterior lights go out and the DRL turn back on. So I assume that eliminates also a fuse issue as the DRL work.
We tried disconnecting the battery for the sensors to reset. I would like to avoid changing the sensor as it seems to be working for all the other lights. I assume the sensor triggers the lights through a relay or the module since all the other lights are working as they should with the auto mode on. Everything works as it should manually, but the headlights in auto mode are the only problem so I assume something is going wrong in the space between the sensor to the headlight relay.