power antenna

[zephyr]

From what I can tell, the stock power antenna has a little control box that completes the power circuit that allows the rod to go up or down.  It's completed when the head unit sends it a signal that says its on.  When the head unit is off, the antenna automatically goes down because the down circuit is always complete.  I just bought an antenna off ebay that has a positive and negative wire and thats pretty much it.  I spliced the wires with the wires that went into the oem antenna (its broken), but it didnt go up when the radio turned on.  It does go up and down but only when i connect the negative wire coming out of the control box, the positive wire going into the antenna and the negative wire going into the antenna.  Very odd.  The negative wire coming out of the control unit always has power whether the car is on or not.
I need to know how to make the antenna go up when the radio is turned on.  I already know that if i buy some extra wire and connect the antenna directly to the head unit i can make it work, but i kind of want to avoid ripping up my cars interior for a stupid antenna.  Any help is appreciated.  Thanks.

[gfisch]

Hmm, I'm trying to remeber exactly how mine was wired.
I dont have the car here, its in NY now, but I believe that the "control box" is simply a SPDT relay. One of the wires coming out of it should connect to +12VDC when the stereo is on and the other should read +12VDC when the car is off. You can checnk this with a multimeter, because I am not sure if that 100% coirrect and if you '93 is like my s14.
If thats the case, the two wires sould connect to the wires on the antenna and the chassis of the antenna should be grounded either with a wire/grounding strap, or by being bolted right to the frame.Hope this helps, if not, try to find a schematic of the cars wiring, maybe on 240sx.org in the faq section.
Also, its really isnt hard to run a wire back there if you just wanna do it that way. Just run it behind the kick panel, under the bottom door trim, behind the panel by the back passenger(dont need to remove it), and down the side of the seat and under the carpet in the trunk. You shoulnt see it anywhere.