I had a stereo shop install a DD w/ the Pac swi-alp module years ago. Just recently all my audio controls, except volume down, is non-functional.

Anyone know what the problem may be and how I could go about fixing it myself?

 

If one function works, at least three should, as there's three functions for each of the two remote wires going into the SWI-ALP, so it's still getting signal on one of those two wires.

My guess would be that the SWI lost its programming, or the SWI unit itself went bad.

You can try reprogramming it (similar to the programming of the SWI-PS) and see if that works to at least get more than one button to respond.

If you can still only get that one button to program, then it's likely the unit is bad.

If you can get three buttons to program, it could be one of the wires came undone, or one of the resistors failed.