1999 S80 Radio wont come on
 

I have a 1999 S80 with about 180,000 miles on it. About a week ago I was seating in it and listening to the radio when I got home. After I finished hearing what I wanted I turned the ignition off but the radio stayed on. I pushed the power button to turn it off and still wouldn't shut off. It was cold out and dark so I looked for the fuse and shut it off that way. Now the radio will not turn back on. Checked fuses, they are good. Took the radio out can't find any fuses on it. Got power to the red wire continuously where it plugs into the radio. Still will not power on. It's the HU 611 radio which has the CD and Cassette player. It does not prompt me to put a code in it incase anyone wonders.
thanks in advance

I'd probably pull the unit out of the car then jumper to the power and ground pins from a direct 12V source to see if it will turn on. If nothing, then I'd simply go on eBay and search for a direct replacement advertised with code (if they show the VIN, tell them to call the dealer and get the code). Market price should be in the 50-75 range.

Thanks will try it out.

Check for power
 

Got the plug and checked for power. Brown wire is the ground. Red is power on at all time. And violet is 12v with key on. so I think radio decided to go out.

The radio came in from Ebay this afternoon. Plugged it in and all good again. Thanks for the help. By the way its a 1999 S80 not 1990