I am trying to turn off the Saddle Valve for our ice maker. I went under the house to turn it off and it appear to be still on. The water is leaking really bad and we no longer use the ice maker on the refrigerator. How can I remedy this problem. Is there a way to cap the saddle valve, because it doesn't appear to turn off? I am truly baffled!!

Shut the water to the saddle valve, disconnect the supply line at the saddle valve and install a cap at the saddle valve out let, see the images below, Thanks.

John