Like Harry said, “A man's got to know his limitations.” You obviously bit off way more than you can chew. That radio belongs in the hands of knowledgeable technician. It’s extremely difficult if not impossible to exchange possible solutions with someone that doesn’t know the basics nor has the proper diagnostic equipment to move forward. Not just one person, it requires both ends of the conversation to speak and understand at least the basic language of electronics, especially with diagnosing complex problems over the Internet. You’re not anywhere near that point yet. Baby steps are involved in learning electronics and that will take some time and effort. I’m sure many on this forum will be glad to help you with your homework if you truly have a desire to learn. If you think someone can provide you with a quick answer to your problem by looking at a video, you’re asking for a miracle.
Step 1. What you saw was not a “jumper” wire, that particular one is better known as a “ground strap “made from braided wire.
