Poured down rain this morning. Windsheild wipers worked great all the way. Untill I parked and tried to turn them off. They won't go off. Even with the switch in the off position they are staying on. Someone please help. where do I need to start to figure this out. To turn them on/off I have the circle band thing that goes around my turn signal lever. its a 04 avalanche. They do turn off when I turn the ignition key off. But with key turned to power, the wipers won't turn off. The delays are not working either. Its only going normal speed or super fast. So when I have the switch set to slowest delay, the wipers are still going a steady normal speed.