Anyway to just replace the rear defroster button/switch on a 99 Camaro. Tried to use it the other night and the button lights up but didnt seem to clear up my rear window. Any recommendations?

 

Turn it on and measure voltage between the supply wire and ground.

 

Did it cycle off after about 5 mins.? If so, then it's the relay in the fuse box. Replace it with a 30A fuse, or another stock relay, and that should do it.

 

actually I dont think I kept it on that long, when I saw after about three minutes or so that nothing was happening i turned it off. I will try it the next time I get to use it. So it should stay on for 5 min then turn off?

 

Just turn it on and check the supply wire's voltage to ground.

No voltage = you have a relay/fuse issue
~13v = bad heating element break or bad ground