Unknown wire plug
 

So my truck is a 1988 GMC R3500 with the 454 in it. I recently replaced the ignition switch under the dash and when I was bolting everything back together I discovered this little plug. It has an orange wire and an orange/brown wire. It’s constant 12 volt whether the truck is on or off. Any idea as to what it goes to?

Re: Unknown wire plug
 

That looks like the plug that was used for the optional digitally tuned radio. Orange wire is live all the time for the station preset memory and clock. Brown wire is connected to the parking lights to dim the display when the lights are on.

I've swapped a couple of those Delco digital radios into older vehicles that didn't originally have them and had to add those 2 wires with that plug.

Re: Unknown wire plug
 

That makes perfect sense because that’s where the wire is, right behind the radio!! It has an aftermarket radio now. Thank you!