Everyone should have a multimeter. They are useful for many things from figuring out if a battery is dead or some fuse has opened. It is not limited to just wanting to repair things. Here is a nice video on the ins and outs of one. I don't recommend that you try to measure AC voltage from safety point of view. Otherwise, it is an excellent and quick video on the topic:
PS the video seems familiar to me so hopefully I did not post it before .
PS the video seems familiar to me so hopefully I did not post it before .