I keep blowing the fuse under the dash which corresponds to lighting the gauge cluster and all the lights on my dashboard. Coincidentally I installed an amp (for a sub) last weekend, and this might be the first time I noticed something which may have happened then. Also, the buzzer that reminds me that my headlights are on when I open the door no longer works. I assume it's on the same fuse.

I found that the fuse had blown this morning. I replaced it and it promptly blew again. Thoughts?

 

The dashlights brightness controller is probably shorting out.

 

How do I remedy that? Is there a way to test to make sure?

Would that make it sheer coincidence that I just installed an amp?

 

Is the amp on the same circuit as the dash lights? I wouldn't think so.

You may have damaged a wire in the dash lights circuit during your work, and it is now shorting out.

Or it's a faulty dash lights brightness controller.