One problem related to horn assembly 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.
Truck was parked in the parking lot at 5:45 am on 12/17/2011 at my place of employment. At approximately 4 pm several employees and I heard what we thought was someones alarm going off. They went to parking lot to see what was going on and saw flames inside my truck around the dashboard on the drivers side. The noise was actually the horn blowing. We did not attempt to open the door, we called the fire department. Upon arrival they put the fire out. The truck had been parked all day & I never entered it after I arrived at work. The truck is destroyed.