S500 trunk will not open

There could be several reasons why the trunk of your 2004 Mercedes-Benz S500 will not open. Here are a few things you can try:

1. Check the latch: Make sure the latch is not stuck or damaged. You can try lubricating the latch with penetrating oil or WD-40, or gently prying it open with a flat tool like a screwdriver.
2. Check the trunk release button: If the trunk release button is not working, it may be due to a problem with the electrical system or a faulty trunk release switch. You can try replacing the fuse for the trunk release or checking the switch for any visible damage.
3. Check the key: If you are using a key to unlock the trunk, make sure the key is not damaged or worn out. You may need to have the key replaced if it is no longer functioning properly.
4. Check the trunk lock: If the trunk lock is stuck or damaged, it may be preventing the trunk from opening. You can try lubricating the lock with penetrating oil or WD-40, or have a locksmith inspect and repair the lock.

If you have tried these steps and the trunk is still not opening, it is possible that there is a problem with the trunk mechanism itself. In this case, it is recommended to have the car inspected by a mechanic. They will be able to diagnose the problem and recommend the appropriate repairs.

When you push button on dash do you hear trunk actuator. Because neither key nor switch works do this. If you can enter trunk from inside car and use a flashlight look around for a pull lever or a button use it this should open the trunk. When you get open replace trunk latch mechanism

see if you can pull the back seat down or remove and there should be a safety trunk release inside trunk which may even glow in the dark.

There should be a manual key hole somewhere in case of a power loss.

ive had this same problem with my 2000 s500 something in the trunk has hung in the latch i used the key and had some help to lift the trunk lid with a little force upward it will come open the net in the trunk gets hung in the latch

To open your trunk there is a lever to the left of the driver seat, on the floor. If you lift this it will pop the trunk. If you have the electronic key fob that came with the car , there is a trunk button on it. If you press the trunk button twice the trunk lid will pop open automatically. You can get inexpensive key fobs on line and program them yourself if you do not have an electronic key fob.

Check your fuse box, look on the diagram and locate the fuse (10 amp most likely) for the auto trunk. The clicking is the relay, it also operates the keylees entry for the doors.

Good luck

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

Try the fuse first. If you have done this than the problem could be in the actuator on the trunk latch. Poss loose/bad wire or faulty unit? I hope this helps!

the key does not work because it never gets used because of the button LOL.check fuses pull switch out jump the two wires trunk might pop if its the switch.
or spray penetrating fluid in key hole and work back a forth a million times.
or go in threw back seat pull off panel and un lock manualy