My rear defrost button symbol lights up but when I click it it doesn’t come on the the light saying it’s on doesn’t come on. I checked my fuses and relays and everything is good. Any suggestions on what else it could be.

 

Try this.

 

You need to probe the power wires on the glass for the heater to make sure there is power getting there. Check the grid for damage (tint removal damage) as a broken line in the defroster will cause it to be non-functional.

 

Power wires are B in the picture, you'll need to remove the back seat, rear deck cover and the C-pillar trim to get to that area:

 

Sorry OP, Did you ever get this figured out?

Are you referring to the orange light that turns when the switch is pressed?

You might be looking at replacing the switch itself. #3 in the picture below.

 

This.
My navigation screen decided to end itself (pixelated pictures) so I bought a used nav screen off a member here and it came with the two button assemblies on the left and right of the screen (#2 & 3). Immediately after installing the entire unit, my rear defroster stopped working.
So I pulled everything back out, swapped just the right-hand side buttons (#3) which includes the defroster, and BAM. Rear defrost started working again.

Not saying this is 100% your problem, but if fuses are good...