stereo dies when i dim interiors

i just got a new system in my car and when i turn on my lights or dim my interior lights the cd player dies and the system shuts off......but when i un dim them it comes back on......also could someone tell me what a capacitor actually does.......thank you

Make sure that the head unit's dimmer and/or illumination wires are taped off and not connected to any of the vehicle's wiring.  Then I'd make sure that the head unit has both a good ground connection as well as a good source of +12 volt constant power.  As a last resort it may be necessary to run a fused wire directly to the positive battery terminal.

And I'm not really good at explaining the science behind a lot of these things, so for the capacitor nitty gritty info info look here.  The part that you'll be mainly concerned with is the section regarding "stiffening type capacitors".  But in a nutshell it stores energy for an amp to use during a brief musical peak and prevent headlights from dimming....but I will not delve any further into the subject of capacitors cuz I don't wanna get flamed for any of my comments.

In a nutshell, capacitors are used discharge power quickly---they can react faster then your vehicles electrical system .  They are only good for short bursts, they constantly charge and discharge.

-Cy