1993 300SD

The keyless on my vehicle does not work, but what I've never seen on a W140 or could find info on is the "Amber" light that flashes in the door handle sensors when I close the locks with the key. (Master Key W/ Remote)

All the doors, trunk, and fuel flap close and open as they should when I use the key. (AND Light flashes green, when I unlock with the key, as it should)

It's safe to say that this is a fault in electronic somewhere. Can anyone shed some light where to begin???

As far as the keyless goes, the batteries have been changed, I tried re-sync but w/o luck and both my Master Remotes do not function on any of the 3 sensors. The alarm does not activate, and this "Amber" light flashed for an extended period of time (approx. 10sec) after I lock with the key.

Are these two problems related? Anyone have an idea?

BTW: Door assist & door lock button on dash works w/o issues.

Cheers.