Tail lights out & Dash lights out also

I have a 97 Nissan Altima. 

The TAILLAMP fuse only blows when I turn on my head lights or turn the knob/dial to turn on accessory. I replacedthe fuse, then turned on my head lights then I heard a POP. Fusebroken again. I even tried a higher 30A fuse and it still pops.

Here is a layout of my current layout and inventions.

A: Unknown female harness hanging around. (Where does this thing go? What does it do?)B: Another Unknown female harness hanging, actually fixed right of the hood pull. C: Extension cord with terminals fashioned to resemble a blade fuse.[ I learned that if the circuit is bad, fuse keeps blowing, then the circuit will have 12 volts going through it. Then a light attached to the extension cord will stay lit and dim/turn off only when your getting close to the short. This is a handy tool to use when finding shorts.][ I also leaned that when a tail light / running light / parking light goes out on Nissan Altimas then the center console will go out to let you know the problem in the rear. ]***FUSE ONLY ACTIVATES when I turn the knob on the steering colum to accessory or lights on.*** I am still confused about the “extra” terminals hanging around. I am still looking for the short. Can anyone tell me the difference between a “short to ground” and a normal short. I am clueless. ThanksSteve

Well... sounds to me like you've got a pretty bad short-to-ground here. The only way for a fuse to blow is if more then it's rated amperage of current is running through it... so it sounds like you've got more then 30A running to ground here. I'm no electrical expert on these sorts of things but it sounds to me like you need to drive down to your car parts supply store, pick up a chiltons manual, and pull your accessory harness. Its gonna be one of those things where you just need to trace the wires out from where you are currently working on. Think of anything you've done to modify the headlights circuit lately. Cut any wires? Things like that? I've only had to deal with an electrical short ONCE and it was a simple fix... my headlight switch hot wire was laying against ground. Just wrapped it in some 3M and all was peachy. --mindctrl

Do not replace a factory fuse with a higher rating.  If you've had a stereo installed without using the proper harness adapter (cut off the factory plug), disconnect the wire you have connected to the black wire on the new stereo and tape it off (isolate it).  Connect the black wire directly to ground and tell us if that solves your problem.My ex once told me I have a perfect face for radio.