My Park brake light wont go off.It will go off with lights on and brakes applied on 2002 Ford F-250 Super Duty

This has me stumped. My park brake light is on and my signals wont work until i turn on my headlight switch and apply the brake pedal. As soon as i release the brake pedal the signals stop and park brake light comes back on. With the headlights on there is also a chatter coming from the 4 way switch. turn off the headlights it goes away but nothing works again... I am so confused and so in need of some direction... Thank you. PS. I changed the brake pedal switch and the brake pressure switch and nothing has changed.

could be your combo switch
1 more answer
In agreement with goodguy,sounds like the multi-function switch.