2001 Blazer Overhead console

When I turn on the car the overhead console dose not turn on until about 30 min down the road. After it finally turns on it works fine. Does anyone know why this is happening?

Pull the overhead consloe, probe the voltage wires(+,-) and see if voltage is resent as soon as the key is turned to the on position. If there is power, then there is something wrong withthe head unit itself. If there isn't power, right away, then you'll have to take a look and see why there isn't voltage.

do you have any tips pulling off the overhead consloe?