The bell dings! Now I understand why the seasoned veterans sit back and laugh. One needs to immerse oneself into the abyss and not give up. Life lesson 7,852. Should I ask this question now? Is this 514th post enough? Please don't hold back...
the service manual is an incredible asset to DIY, of all varying skills.
if you’re a beginner in DIY, reading through the relevant part for your problem can help you decide if you have the tools and ability to fix something or if you’re completely in over your head that you need to take it someone else.
if you prefer changing parts on cars, looking at the relevant sections will tell you what parts are involved. It seems that every week on this forum I’ll see someone say something such as “my X doesn’t work, a neighbor says that it could be the Y. I changed Y, and the X still don’t work”. Well, if they had looked at the manual, they could have realized that X and Y are completely unrelated and the neighbor had no clue.
if you want to diagnose, it’s pretty much invaluable, as it tells you how a system is supposed to work as well as how to figure out if it’s not working.