i have an A class 160 and central locking on a rear door isnt working. how do i remove panel to get to mechanism?

 

i have an A class 160 and central locking on a rear door isnt working. how do i remove panel to get to mechanism?

 

To anyone else who was struggling with this problem as I was for half an hour today, the answer is: change the batteries, then re-synchronise the locking system by aiming the key fob at the rear-view mirror and pressing the fob button twice.