Yes, even if fuse size is different if you have power at the ylw, red, and good ground at the black, then the H/U is probably bad. Last check before taking it back would be Kranny's LFC. Unwire radio, hook up ylw and red to batt +, and Blk to Batt - . If it still wont come on its definiteley bad.
If it now comes on then start over at wires checking ground first.