Car Stereos: no power up, sony cd player, hi boss

Question
installing new Sony CD player - removed old sony CD player & old JVC cassette player -- none of these will now turn power on - test light shows power on red wire to unit - proper ground, same as been used for years - what could this possibly be???

Answer
Hi Boss,

What does the test light show on the yellow wire to ground?  It should have power too.

If it does, and your harness is wired correctly, put back old sony cd player.  If it works, you probably got a dead unit -- it happens sometimes.

Justin