Op needs to go to a stereo shop and get this fixed for 50 bucks or so.
Toners(mine doesn't need a ground clamp, it's so handy) and lamps and multimeters are for semi experienced people not people who ask the most basic questions when their rig isn't road worthy.
Go to stereo shop, get it fixed then watch you tube videos for education about the next MORE MINOR problem.
This one could be a anything from a rubbed wire in a spot you'll never be able to reach to a problem in the steering column you won't be able to diagnose.
Also:
Amazon sells resettable fuses with a little button on them. They're circuit breakers that fit in fuse holders.
It's a lot easier to push a button than to mess with fuse pullers.....