After i posted i thought it might be the battery exploding. i got the car home now but i have not been able to get the trunk open. No power so the laser key won't work and i can't get the mechanical key into the trunk lock. it slides into the door lock fine. i just squirted some pentrant/lubricant in there. hopefully it loosens up. Not sure if its the original battery. i bought the car from an independant dealer ayear and a half ago. I do have the repair history from the original MB dealer. i will see.