No sound from speakers

Did you just install the radio? if you did make sure you get all the right color coded to the right speaker. I don't know of any car radio would have relay install, fuse would be more like it and more safe when it come to sensitve electronics. did this problems just arised or you had for awhile and now it just quit. If the systems has been in the car for while and it just started to happens than you may have bad connect to your speakers, check both post + & - making sure they have good contact; check to make sure speakers is good and not blown. check & trace the speaker wires making sure is not cut from pinching. if the wires check out than you have an audio problem from the unit it self. most of the radio equip with 2 fuses, one internal and external. if the radio has no warranty left on it than you can open the cover up and check making sure fuse looks good. if its still under warranty, do not mess with it, take the unit back or contact manufacture company how to ship and where to ship to. I hope that help some..good luck!!