I have a perplexing problem with my 2000 F150. Monday morning I woke up to the news that my headlights were on. I knew that they were off the night before, so I was wondering what was up. I went out to my truck and low and behold, the headlights were on. The truck is locked with the keys in it (I have the keypad mod), so I was scratching my head. I unlocked the truck, and jumped in and the light switch was in the off position. I played with the switch for a while and at some point the lights went out. I thought that this was strange, but an isolated incident.

Later on, I went to get into my truck and the keypad wouldn't work. No power. I figured out how to pop the hood, and hooked up the jumper cables and got in and started the truck. After that I tried everything imaginable to get the headlights to turn off. The only thing that worked was pulling the fuses for the headlights and parking lights.

After stopping at the Ford garage and getting the schematics, I went to troubleshoot the problem, and the lights were back to normal. Then this afternoon, pulling into work they were on again, and shutoff while I was standing next to the truck.

The truck does not have Autolamps or DRLs.

Any thoughts?

Thanks,
Sven

 

i would say head light sw. not sure what watt those after market head light bulbs are. but have seen many burn up head light sw's. and sometimes multifunction sw. i would start with head light sw. see if you can see any burnt or melted wires on back of sw. good luck.

 

Thanks for the reply, but it was not the headlight switch. I could disconnect the switch completely and the lights stayed on.

I did some more investigating last night and found that eventhough my truck does not have the autolamp option, the relays for autolamp are installed. I pulled these relays and it fixed my problem. No more phantom headlights, but the switch functions work fine. I don't know what is energizing the relays upstream, but at least I won't have to worry about a dead battery.

Sven

 

well good atleast your not dead in the water. if the realys are there. look to see if the module is there. if you have time. you should be able to look from under the left front. in front of the tire. just in front of the fender well. a small elec. box. mounted to the core support. it seems funny that both relays stick on at the same time. just a tought. gald your ruuning.