I'd like to have my radio stay on after key-off (on a timer or with the door opened). I've been contemplating this mod for a bit and found some info HERE. A few questions: Should I use the dual relay option or the triple relay option? Is there a way to add a timer to this circuit?

I would also like to add a timed/fading dome light that would shut off with key-on. Could this be added using a similar circuit? Any help would be appreciated.

 

Any help would be appreciated.

 

Omron makes a time delay relay, H3Y, they come in different voltages and timer lengths, I have used the 110vAC versions with no complaints

And they are inexpensive

2001 Ranger Door Ajar switch uses GROUND control
Door Closed has switch unGrounded
Door Open Grounds the switch-wire to GEM

So you could find that wire in driver side kick panel and use it for Door Open detection, in 2000 it was a Yellow/black stripe wire, not sure for 2001
You could use that Ground to activate a relay, but when door was closed again relay would deactivate
So you would need at least one more relay, because to do what you want requires you to give radio full time 12v power not just key on power like it has now
The Key on Radio power wire could be used to "reset" the relays