guys... I was under the impression that only the new SMART key cannot be reprogrammed as the key is coded to the car. I am not aware that even the BLADE IR KEY cannot be sync to a different car. Can someone confirm?

The car in concern is a 92 W140. The Sync method is pressing the key and turning the lock on the door. However I could not sync a different key I got from EBay to my car!

Cut the story short, I super clue my original IR key as the casing was falling apart. However the fume from the glue killed my remote. I now cleaned the electrical board up so the red light comes on when I press but somehow I can't get my car to recognise it! Did I kill the key or you guys have a solution?

please advice. Thanks