Buick/Olds: electrical, ac/heater blower, woven cable, gm products

Question
When I shut off my car and take my keys out my ac/heater fan keeps blowing. I had to disconnect my battery to make it stop.  Also, with my car running I can no longer turn off the fan even.  Also, my cruise control recently stopped working and I keep blowing fuses on my brake lights.  I am assuming there are loose wires and my fan blower wire is now grounded that is why it won't shut off.  But where do I start looking to find my wire problem?

Answer
First check the engine ground wire...it should be near the back of the engine, a sort of woven cable, attached to the engine block and the frame.You definately have a "crossover" problem...which is typical for GM products.Often, when there is a problem in one circuit, it "crosses over" to others, alerting you to the fact that there is a problem. Check all fuses, all circuits, and any wiring you can access, to see if there is a loose connection or a grounded "positive" lead.