wot type of radio is it some have a fuse on the back of the radio which blows and the one in your fuse box is ok or you can try getting a multimeater or a 12 volt builb and turn the ignition on with the radio unplugged find the red and black wire from the radio making sure its the right red wire put the builb across the red and black wire if it lights up the radio is naffed
dave, October 2012