hi this is my first post i hope you guys could help me here
when the radio is on ...and when i try to switch the rear defrost on (for rear windows) i lose my radio ....any idea? i have 2002 impala thank you all

 

Check the grounds for the radio.
66ImpSS396

 

do those year impalas have an external antenna- or is the antenna built into the rear window.
the 2006/2007 impalas have the defrost grid- and radio antenna on the back window.
ive heard of people getting tint (metallic tint) and the radio reception going bad.
maybe you have tint and the defroster and antenna are making contact thanks to the tint?

 

I know I'm a few years behind on this post. You probably have it repaired by now, but if anybody else should find it such as I did, there is a module on the rear window very top, not in the Middle with a grit is it's at the top on the driver side, left side of the window. First, you have to remove the C pillar plastic molding to get to the electrical connector. There should be a white and a green wire in the connection.
The white has power all the time with the radio, the green one switches with a defrost. It goes to the module and then to the rear window and the antenna if that module is bad you'll get this issue.
​​​​​​ There is a gray cable for the antenna the sleeve pulls back to disconnect from the module, that is screwed onto the lower portion of the C pillar by the rear window.