car wont start, clicks with intermittent horn blowing and radio sounds.

Hello, I challenge the thought that the battery is fully charged. This sounds like a voltage issue. Either the battery is not fully charged, or there is a high resistance level in the cables causing an interruption in the amount of available voltage for the different electrical systems to utilize. Hands on testing Is needed. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops