With my corvette 1990 I have no power on the wiper and my fuse is good? can you help me. Thank

Is it an aftermarket radio??? Normally they have a 5A fuse on the back of the unit itself, or in line of the radio's power wire.

It would have to be in the ignition switch,this ,when turned on,sends power to the fuse.

Check for power at the wiper motor. The door is vacuum operated the wiper motor is electric. If there is power present the motor is bad, if not check the fuse, and then check the wiper switch. My guess is that the wiper motor is bad.

check the low side switch located on the ac receiver drier for 12 volts if so jump it with a paper clip if the compressor comes on then the relay is good if not the relay is in the fuse junction box under the hood.Most likely the pressure sensor.

Sounds like the wiper motor is shot. You can check for electric voltage at the motor using a meter to make sure it is getting power first.

If the Fuses are good and the Rear Works the Cause will be the Wiper Motor for the Windshield Wipers. Please Rate My Response! Thanks!

Check under the dash or on the sides of the dash with doors open, or under the hood in a box marked fuse relay. In most GM cars and trucks these are the places where thay stash the fuses

These may be switched via a relay that has failed; fuses are for protection but relays likely handle the current those draw. It's conceivable that all those have 12V made available when you turn on the ignition and then fused by the individual circuit thereafter.  I'm pretty sure Haynes or Chilton publishes a service manual for your car and they contain detailed electrical diagrams along with complete mechanical data and repair instructions.   

The filter is underneath on the passenger side behind the front wheel. Release the pressure first, or you will get sprayed with gas.

This may be fuse blow out or may the display is defective in the circuit...........