Sony CDX-F7005X CD Player "ca850" Questions

radio audio working but no audio from CD. Shows cd playing but no I installed a CDX-CA850 in my grand jeep cherokee. The radio works fine but when I put a cd in, there is no audio. It shows the player

sony cdx-ca850 hi just wondered if anyone can help.i took the sony from a car i sold and left it in a locker in my kitched ready to fit to the next car but that was there for about a year,now i fitted