95 T&C electrical problem

I have a 1995 Town and Country that has a strange problem.A couple of weeks ago I got in the van and had a dead battery when I went to start it.I put a battery charger on it and when I went to try to start it again I noticed a little smoke coming out of the dash around the radio.After that I noticed the digital dash was not working.I also noticed the electric door locks,radio and the overhead lights would not work.I checked all the fuses in the van and under the hood and all appear to be good.After I unplugged the radio I took a test light and found that the memory hot wire had no power and the switched hot wire has power with the key on.A couple of days later I for some unknown reason decided to put an aftermarket radio in it.I hooked the memory and the switched power wires together and when I plugged the radio in and turned the key on I notice that the dash is working as is the dome lights and the power door locks.If I unplug the radio everything quits working again.I am not much on electrical and am hoping someone out there might have an idea as to what is going on here.By the way,I found that the radio that was in the van when the problems started is probably what did the smoking as it no longer works.Thanx for any info!:banghead:

Hi ninemmeter,
not familiar with the system you are working on, however from a troubleshooting stand point I'd say that the radio is now supplying the ground for the system when you hook it up, perhaps the smoke you saw was from the original system ground being loose and arcing.