1990 Totota Supra AC and instrutment lights work with key out

1990 Toyota Supra When I turn off and remove my keys, the car turns off but the instrument panel lights and heater/AC fan system still works. It's not everything that works (the radio does not work). Sometimes when I restart the car and turn it off again it all turns off like it should, other times this does not work and I have to disconnect the battery. Again sometimes when I re-connect the battery everything is off and sometimes the instrument panel/AC fan is still on. It's not the turbo timer because I've completely removed it with the same result. I'm guessing it's a faulty relay somewhere. Any ideas where to look?