Radio ga ga....

This will be easy fix for those clever people that know about electrickery.
I thought radio had packed up as was lighting up but had no volume. While driving i gave way to another car and flashed headlights to them.. suprised when radio started working. Have checked flasher bock on steering column and can see black and purple wires going to connection... is this correct.? Also when lever is pulled back i can see spark when contact is made ..
Csn some one give me an idea before i go up in smoke... cheers..