Just got in my truck today and when I turn the climate control on (A/C) it will turn on for a second and then turn off for a second then back on, then off etc (in a pretty constant cycle). It also sounded like the cd player MAY be doing the same thing. The radio and clock seem to work just fine. Any ideas? It is a 2004 f-150 lariat with 50,000 miles. Never had ANY problems concerning this before.

 

I also noticed when I put my key in the ignition before I start the engine the climate control panel will flash on then on and cycle that way. I am starting to think it is an electrical problem but I am not sure what would cause the cycling.

 

I had the same issue as well last week. First it started blowing warm air. Next day I go to put in my key and the climate control starts blinking and making a noise similar to a CD. I started the truck and the climate control would not turn on. Restarted the truck and it worked fine for over a week. I read somewhere that if the climate control is blinking, it is throwing a code that there is something wrong with the system.