One problem related to brake light switch has been reported for the 2004 Ford F-150. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Ford F-150 based on all problems reported for the 2004 F-150.
2004 Ford f150 w/ adjustable pedals - after a few years use, the brake lights do not work properly. The lights will come on, but only under extreme deceleration, hopefully. The lights will reset if the brake switch is unplugged and plugged back in with vehicle running, but then will continue to act unreliably after a few days of use. The brakes continue to work along with the switch to reposition the automatic shifter from out of park, but the brake lights are completely unreliable. I visit an official Ford f150 forum with many other members that several others are starting to notice that their trucks are doing the same thing. Replacing the "brake switch" recommended by Ford did not correct this problem. This problem has been reported on the forum by members with 2005 and 2006 models as well.