No, you can not open the trunk. I speak from experience.
My 04.5 C 230 SS had this happen. I was packing my trunk for a road trip. I left my car for a little bit so I locked it up. I came back later to put one last thing in the trunk. I popped the trunk with the remote, but still leaving the alarm on. I put my key in the trunk and shut it by mistake.
If you have Teleaid, they can unlock yoru car that way. I don't have Teleaid, so I had to get an emergency tech sent out by MBUSA. He popped my door open and disconnected the battery.
When he first opened the door, my alarm went off, and you could not hit the trunk release. It would not function with the alarm going off.
Hope this helps. Learn from my mistake people
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