Check the water valve under the refrigerator. It could very well be on the valve because of a bad or loose fitting. Put some newspaper down under the refrigerator so you can see where the water is coming from before you turn on the water. After you find and fix the leak make sure to clean the coils. Those plastic fittings will leak if they are tightened too much, which is a very common error. You snug up the fitting and tighten about 1/4 turn more, then check for leaks on the plastic fittings. When I am using those fittings I always get some extra ferrules because they are very easy to ruin and you have to replace the ferrule if you over tighten the compression fitting.