I got a bad relay that's draining my battery- so I bought a new one on ebay, and have it in my possession... is there any tricks to changing it? I know exactly where it is, and it looks just like a plug to me. I'm know I should have my car turned off- should I disconnect the battery? Just plug it in?

Thanks!

 

It's better if you disconnect the battery terminals to avoid the short circuiting during the procedure.