Nissan Repair: 1997 nissan altima, nissan altima, fuse block

Question
I recently replaced the radio.  I think i might have crossed a couple of wires to the interior lighting.  when the light switch is in the parking lamp position nothing comes on. When it is in the head light position the head lights come on but nothing else.  I replaced the fuse which is not blown.  Is there a module that controlls the power to the switch or to the rest of the interior?  I have a manual and the diagram has a block on it J/C-6 is what it is called i think it is just a connection point.  I would appriciate any help in the matter.  The vehicle runs fine cant drive it at night though.

Answer
Craig,

Nissan uses a floating grounding system for the radio.  When you check certain wires with the key off they are grounds and when the power is on they turn into power.  I would go to a radio shop and get one of those connectors that adapts to the factory plug.  Reinstall the factory plug and solder in the adapter to the aftermarket radio.  Otherwise, you can get a wiring diagram/schematic and suffer through getting the wires corrected.  Another way to do it is to insulate the wires coming to the radio and then wire directly to the fuse block for power, switched ignition and ground.