91 vw passat electrical problem

I recently installed an aftermarket stereo on 91 passat .
It was working fine for 1 day.Than started having problems with my instrument cluster ,door locks and Cruise control .
Does anyone know what the problem might be ?

Never mind the problem i got it solved it was a short in the trunk light.
Replaced the blown fuse #20 im all good now.
All of the above components seem to be running off a same circuit.