Welcome to the forum! I'm sure you'll be up to speed with the capabilities of PicoScope if you are doing a lot of diagnostic work but there is plenty of information both here and on the website. Please see below for a link which contains what we believe are useful posts to help with our diagnosis along with different techniques.
Hopefully this will help you to get started but if you need any assistance then please shout. We're all in this together and if we can help then we all learn in the process!