Blinkers and heater

a few days ago i found out that my heat and blinkers do infact work after a while of thinking i was gonna have to pay alot of money to get it fixed but the problem is is to get it to work i have to hit underneath the steering wheel and the il hear my heater kick on then my blinkers work what causes that

A loose connection.
possibly at the ignition switch, but there are many others.

im sory to keep bothering you im just tring to get my 87 ford mustang coupe on the road instead of having to sell it at my ignition switch there is a black wire that is for some reason not connected i dont want to connect it because im afraid it might mess something up but the other side where i am suppose to connect it to is still there do you know what that black wire is should i connect it

Slick, Hitting It Does.