Join Date: Nov 2015
Location: Washington, D.C.
That black wire, which is usually black with a yellow stripe is how the ignition switch gets power. It runs from the positive side of the solenoid as a black-yellow and turns into the yellow wire going into your ignition switch. Even if you grounded that wire instead of hooking it to the positive side of the solenoid, I don't believe that would necessarily harm anything. It's only hot from the battery and doesn't get power from anywhere else.