I'm helping a friend out with his fridge. (What a great way to learn how to do this stuff.)

It's a side by side. I haven't seen the fridge myself, but he says it runs constantly and the freezer side collects ice on the bottom. What do you guys suggest that the problem is?
I read that ice build up can be caused by a clogged drain. What do you all think?
I was told the door seals were fine and I told him to clean the coils off. Anything else that it could be causing the constant running?
Model#
KSRP25FNBT00