W210 door lock

[dubadaddy]

Having problems opening the car via the key and the electronic door handle on my '97 E420. I have changed the batteries in the "key" and its seems to work fine pointed at the front windshield. I have notice that the door handle "window" for the lock and the trunk lock has gotten "faded" and I am thinking this may be the cause.

Has anyone repaired/replaced these before and if so has some sort of DIY fix that I can do? Maybe some 2000 grit wet sandpaper will bring back some of the clearness to the thing?

Thanks in advance.