I performed the Aux/Mod to my 99' C5 Bose Stereo with CD. I followed the post to a T. I installed everything and when I went to use it, the sound was only coming out of the passenger side speakers. So, I figured no problem, one of my connections must be loose. Also, the lights on the numbered buttons weren't working. Again, I figured I'll just take a look. I took it out today, took it all back apart, looked it all over, and saw nothing wrong. I pushed on all of the connections I disconnected just to verify and everything seemed good. I put it all back together and re-installed it. I turned it on and the lights on the buttons are still out... but here is the weird part... The sound is now on the drivers side and no sound on the passenger side. I verify this by using the balancer ****. So now I'm thinking it must be a loose wire or something on one of the plugs on the back. I unplugged everything, wiggled the wires, pulled on stuff... unplugged and plugged back in. I just can't get the sound back on the passenger side. I'd like to be able to get the lights back on... but I'm more concerned with the sound. Anyone have a clue as to what to check or look for?
I'm thinking that I might eventually change out the stereo and the speakers... but for right now, I just want to have the tunes back on!!! The Aux/Mod works fine too!

 

You did something wrong or you would not have this problem. I don't have the schematic of the unit to help.

You may have followed the instructions but apparently affected other circuits somehow.

Sounds like unintended consequences. It happens to all of us at one time or the other.