Is there a way to troubleshoot/fix these LED rope lights?

[Flyover]

Hah, this rope is 48 feet long. Here's hoping the problem is in the ~8" power cord!

 

[oldognewtrick]

Test your plug for continunity, if the plugs bad, send me a private message and I'll mail you one. I have several.

 

[Flyover]

Seriously?! That's incredibly kind of you, @oldognewtrick! Thanks.

I haven't gotten around to any of this yet (my multimeter is still packed in a box) but I'll try and hurry up and find it.