My automatic headlight fuse blows every time they cut off. They will come on, but when the light sensor tries to turn them off, the fuse blows. Is there a relay? If so, Where is it? Anyone know?? Could the light sensor switch cause this?? I changed the main headlight switch, and it did not solve the problem.
I'm about to blow my own fuse over this!! HELP!!!!!

 

You need to identify what year your truck is in your post....

 

SORRY!! My truck is a 2002 f150 super crew 5.4 engine.

 

Which fuse, specifically? There are five fuses in some way involved with the autolamp system, more if your truck has DRL.

Does it matter if the MFS has low or high beam selected?

Have you had any unusual activity with the O/D light on the transmission selector. Has there been any correlation with moving the lever and the fuse blowing?

Steve

 

The only fuse that blows is #29, which is the autolamp module, transmission overdrive control switch, central security module, beltminder fuse. It also is the fuse for the automatic door locks, but I disengaged them as per the owners manual. When I replace the fuse, the lights come on automatically as I am sitting in the dark carport, but when I back out and light reaches the dash sensor (or something else), the fuse blows.

 

...and the rest of the questions.....

 

There is no overdrive light activity. The lights work on high beam and on low beam. I tried them again this morning and they blow the fuse as soon as light hits the sensor in the dash that turns off the lights. I used a flashlight on the sensor as it sat in the carport. Am I right in assuming that that light sensor switch is shorted?

 

Probably. I don't see anything else in the circuit that would make any sense.

Steve