2000 s500 mercedes making a beeping sound why?

SOURCE: trunk qill not open

Your trunk lock actuator is probably in valet mode. Take the mechanical key out of your smart key(should have a release button on the bottom of the key which will allow you to slide the hidden mechanical key out of the plastic housing) insert it into your trunk lock actuator and turn to change your function of trunk actuator. In the valet mode the trunk does not respond to your central locking or release button commands. Your owner's manual will tell you about these features. I hope I have been helpful

SOURCE: I have a 2000 Mercedes S500 (W220) with a Bose

hello,good day,yes your may check the power supply and contact,if not corrected,send your car to a dealer for proper diagnose,maybe erase fault or configuration of your system is needed,to correct the problem,ty

SOURCE: fuse schedule 2000 mercedes s500

It should be in the Black fuse box next to the Brake Booster. Open the lid, under it you willl see the diagram of fuses to replace. Good luck.

SOURCE: My powerlocks on my mercedes 2000 s500 wont repond

REMOTE KEYLESS ENTRY BATTERY IS WEAK OR DEAD.YOU HAVE TO LET DEALERSHIP REPLACE KEYLESS ENTRY AND REPROGRAM IT TO UNLOCK OR LOCK DOORS.

SOURCE: My 2000 Mercedes Benz S500 is dead- electronic key does not

It's not that unusual for a battery to fail that soon, and the "no lights, no nothing" says that it's the battery again. Your best bet at this point is to pull the battery and take it to the point of purchase for testing. They should either replace it under warranty or charge it for you. After you replace the battery you should have the charging/electrical system checked for possible shorts or power drains.
BillB