LED dome light, other parts not working??

[mmaxeyjr]

Me and a buddy made a LED dome light w/ a circuit board and solder.

I was putting in my led dome light and it flashed on for a second then it turned off instantly.

So to test if the led worked itself I touched the ground to the ground on the battery and it flashed on for a short time then off.

Now my headunit doesnt work and I also noticed the trunk lights dont turn on. And theres a humming noise when i turn the key to on.

I checked some fuses, but they all seemed good and not blown.

Any ideas?

edit: also my automatic seatbelts wont work unless the key is in the ON position. If I turn it off and open the door the seatbelt stays back instead of moving front.

thanks