Frustrated by dealer service

[RMachida]

Took my truck in because the horn was going off on its own whenever it got really cold. The service writer said they couldn't work on it unless it was going off. So had to make appointment after appointment until the date matched the weather. They didn't get around to it until the next day and replaced the FCM plus said I needed a new fuel filter and fuel system flush or jeapordize the warranty (filter was replaced 2000 miles before this). After picking up the truck, the horn still didn't work and now the fog lights don't work as well. Took it back and three days later they said to pick it up since they needed to order a Power Distribution Center. They seemed more concerned that I needed all the fluids changed out. Truck has <15k miles. Next appointment is on the 20th and I'm almost afraid of what will happen. Also several mounting screws from the PDC are missing. Just seems sloppy, minimal quality control, and sub-standard customer service. This is a five star dealer that I thought was supposed to be pretty good.