Have checked fuses in front of battery.Have checked fuses at left in trunk.Side mirror heaters are working and about 4 of the bottom rear window lines.what else.

 

Was the car ever tinted? check each line, maybe a line got damaged somewhere on the window.

 

The rear window is dark.I don,t know if they come that way or was tinted.

 

Your window has been tinted....factory glass is clear...you might have to remove the tint to see if the lines on the glass are damaged.

 

If the bottom part works and the rest doesn't you have a cut somewhere in the heater circuit on the window. It is strange that it would happen some random time after tint was already applied if anything the tint would protect it at that point.