HK3480 Blue Volume Selector Light Quit

SOURCE: harman kardon avr500

Your drawing to many watts from the unit and its shutting down. Make sure the -/+ are set properly for the speakers. Also the power amp inside the unit could be bad and the relay trips off. Plug straight into the wall and don't go through a powerstrip. Is anything else connected to the receiver?

SOURCE: blue light

blue light on volume knob not lighting up

SOURCE: will no turn on

I have the same issue. I have a 7.1 AVR 235. Im good with a solder gun. Any recommendation on how to repair this problem? Im sure its way out of warranty too.

SOURCE: volume display seems backward

This is because the volume knob on ANY stereo is actually an attenuator.  Meaning, the stereo would play at full blast (way too loud!) if left to it's own limits of power, so your volume knob is actually "dialing down" the power, or when fully turned up, letting it all flow.
The reason that the numbers change like that is it's showing you how much attenuation is happening in decibels, or dB, so for insTance, when it's at "-30" that's a pretty decent volume, but at "-5" it's much louder and your neighbors might complain.  I think you'll notice that it can be cranked to something like "+5" which on my AVR 100 will blow the speakers.
In other words, this is normal, so relax and enjoy the music!

SOURCE: Function Selector Bypasses Input Sources

Hopefully this post isn't too late... That receiver has the ability to disable certain inputs. The easiest thing to try is to do a factory reset.
1. Turn off the receiver
2. Hold down DISPLAY and PANEL UP/DOWN buttons and press power.
3. All Clear should appear on the screen.

Unfortunately, this clears out all of the other settings on your unit. It should, however, re-enable the inputs.

Let me know if this helps!