stereo sc811 wont power up. security light flashing.

[BEJinFbk]

If I were in this position, I'd unplug the changer,
then check for power on both of the pins where
it should be appearing at the main connector.

Your radio gets a constant supply on one pin and
a switched supply that comes on with the key.
I'd give you the pin numbers, but right now I'm
sitting in the Anchorage airport with limited
resources. The fastest check would be having
a quick look with a meter. Good Luck!