Okay, [link|https://www.youtube.com/watch?v=QY8Ajk5JJUk|here|new_window=true] is a video demonstrating how to use a dock flex tester. The video uses an iPhone, but all of the dock flex testers are identical except for the USB connector. You will most likely need a multimeter (or an oscilloscope [or both, if you’re ''really'' serious about getting into electronics. I got an old one for $15 from a local college selling one on a government surplus website.]).