Handbrake arm, rear calipers

My 200 is giving me lots of grief at the moment, decided to look at the first which is a locking wheel at the back. I looks and the handbrake isnt releasing after being on, now it looks like its the arm that is siezed up, but im thinking its maybe the cable itself is siezed inside the casing that it has? Anyone had anything similar? Its hard to tell, i am hoping its the arm on the caliper because renault have already said they will replace on warranty if it is the caliper, any input appreciated!
 
Hi
Good news it is not the arm but the cable. Remove the cables and make a funnel from some Blutack, then run engine oil down the handbrake cables. It is common problem. Cable get water in and go sticky. You may have to pull the nipple out of the cable with some pliers and work the handbrake with a friend pulling the cable in and out.