i have a xc 90 that i cant get the radio working.. it has to be the power source as i tried the radio in another xc 90 and the radio is working , the fuse is fine, any help in what could be the problem and where i should look for the issue would be much appreciated

 

I'm not the xc90 guy but most radios have two or three sources of power. One for the radios memory. You plug it in and it might light up but that's not the power for the actual operation. There might be two different fuses.

The third power lead would be for lights or dimming. So when checking for power you need to know what color wire you're looking for to check power.
Same with fuses.