How to get my car cd deck isn't working

Question

i tryed to install another after market deck into my car but could not get it working... so i took it out and put the old deck back in but then could not get that one to work... how could i get it to work?

Answer 1

If one of them was known to work before, you have a wiring problem.

Check all of the fuses first. Then check the ground. If you have a multimeter it's a little easier.