There seems to a problem with the trunk. What started the alarm sequence was after the car was locked (and alarm set) I tried to open the trunk with the key. That set off the alarm. I had tools so I was able to disconnect the negative cable.
Then I tried locking and unlocking the driver door with the cable connected. Also i tried turning the key to on before I reconnected the cable. Bothseemed to work, but when I tried to start the car it wouldn't start and the alarm went off.
I Haven't tried locking and unlocking the trunk, although that seems to be the area that causes the problem.
Sorry for the delay, I had to go back where I left car to get VIN.
I don't know what body style it is, but it is the small 4 door. E300 should give you the body style.
The VIN is WDBEB31E4SC186475
No it will not crank. It will pre-heat but when you turn it to the full start position it does nothing -- then after a moment the alarm starts up again.
I did not try the trunk. I'm assuming to try it I must connect the battery, otherwise the brain would not detect the locking and unlocking.
I can go back and do that if appropriate.