My rear windshield defroster is not defrosting... Does the grid on the glass have any effect on that operation?? The reason i ask is b/c when i got the car the tent on back glass was messed up (bubbled-up) my uncle scraped it off and didnt do a very good job of it maybe he scratched the grid but i need you guys to tell me does that have anything to do with it not working????

 

Yes, that grid has everything to do with it. A lot of people who do know how to tint those types of windows correctly will get the bubbles all in them. And you cannot touch those grids with any sharp object or it will cut that grid line and no heat will transfer through, hence your rear defroster problem.