Wiring nightmare

Hey guys! A couple of months back a couple of thugs boosted my 200SX and raped the hell out of it, stole my stereo, burned the clutch, etc.
Anyway, I have a new unit, but I am faced with a salad of wires that I don't have time and patience to sort out. If anyone knows which colour(s) correspond to which speaker(s) and so on, I would very much like to find that out. The car is a 1985 200SX (in case the wiring differs from year to year). Thanks in advance!

to be honest.. it doesnt really matter which colors you put to what as far as the speakers go.. i mean as long as positive goes to positive and negative goes to negative they will work,.. the only thing it will mess up is that when you go to change the balance or the fade, you may notice that both right sides are on the left.. or vice versa.. you get the idea tho?.. but as long as its just the wires for the speakers.. and not the power cables you'll be fine just hooking up the pairs up to whatever other colors

have you cut the harness from the car? if not just get a wiring harness and do it up that way.

have you cut the harness from the car? if not just get a wiring harness and do it up that way.

I don't understand what you mean... they took the old unit and the harness, I'm just left with a bunch of wires hanging out of my dash. I suppose I'll just have to do it like henge says, and hope for the best. What gets to me though is that there are a bunch of wires I never used to begin with, a lot of black ones with red stripes... some pink ones... like I said, a mess

gimme a few and Ill find you the wiring diagram. I just have to search through the bookmarks.

A HA! Once again. Yellow saves the day. If this cant help you, I dont think anyone can help you. Go by the 1985 model obviously.

http://www.installdr.com/Harnesses/Nissan-Wiring.pdf

also.. what you can do.. if you have one of those wire tester things, check to see which wires has power all the time, that will be your 12v constant which on most wiring harnesses will be yellow, then find one that has power when you turn the key in the ignition and that will be the 12v remote and will be red, then on the wiring harness the rest should be for the speakers and it sometimes has a blue wire which i believe is for the power antenna, but since our cars dont have em you wont need that

okay...heres something i learned..its to test a speaker for on/off functionality, but it'll help in your situation...
using a 9V battery, "click-Test" your speakers..simply put the positive wire of the speaker to the positive of the battery, same for negative side..if it clicks (pops, dont worry, it wont hurt it if you just touch the wires to the terminals) then its hooked up right, if not, try another wire! I suggest doing this only when you know for sure you have the speaker wires separated from the rest..

*cough* multimeter *cough* ...

Wiring a head unit from a bunch of wires is incredibly easy even without a diagram if you take your time ...

First, make sure you don't have any blown fuses in your fuse box ... If you do, before you replace any, make sure no wires are grounding out ...

Next, make a new ground, junk the stock one ... Use 12 or 14 gauge wire depending on your head unit (Alpine recommends 10 for their V-Drive units which is overkill unless you listen at very high, very distorted levels for long periods of time). You'll need a ring connector that you'll want to clip part of the end of (like the stock one) and you'll want to find a place that has a bolt into the chassis. Sand that spot until it's shiny, slide the new groud wire in and tighten the bolt ... Ground is taken care of ...

Then find your constant ... With the car off, touch the negative lead of your multimeter to your new ground (the wire, not the place where you bolted it as that might be kind of awkward :p) and touch the positive lead to every other wire there until you find one that reads 12.X volts (if it reads lower than 12 volts, have your battery/multimeter tested). Constant is found ... If you choose to upgrade your constant wire (for a higher power head unit like an Alpine V-Drive), tape this wire off and run a new power wire to the battery (with an inline fuse, of course). It's very important that this wire not touch ground because, at the very least, it's going to blow a fuse ... if it doesn't trip the fuse, it'll start a fire ...

Next step is to find your ignition power. This will only have 12+ volts on it when the ignition is set to accessory or on. Turn your ignition to accessory and, while holding the negative lead to ground again, test each wire (other than the constant) until you get a 12+ volt reading. This is the wire that turns your head unit on when the car is turned on and it's the wire that turns your head unit off when your car is turned off.

Well, now we have the basics ... To find your speakers, use a battery ... DO NOT USE A 9 VOLT BATTERY, THOUGH ! I forget what resistance our speakers are, but if they're 4 ohms, 9^2/4 = 20.25 watts (ohm's law) and, don't forget, 9 volt batteries tend to actually be 9.6 volts, so it's actually more like 23.04 watts into 4 ohms ... so not good for our stock speakers (if they're 8 ohms, then it's 10.125 watts and 11.52 watts, respectively, still over the nominal power handling) ... Also, you'll want to make sure of the polarity (the speaker should move out, not in), which means you'll have to remove the door panels to see the front speakers ... speakers out of phase = cancellation = awful sound and low volume ...

i used the battery trick before but used a AAA battery at 1.5 volts and it worked fine.

I use a D battery ... Using a 1.5 volt battery (alkaline = 1.6 volts, rechargable = 1.2 volts), you're looking at under 1 watt with any normal speaker ... Very safe ...

I use a 9 volt battery to test subwoofers because they're less efficient and a 1.5 volt battery really won't move one ...

yeah, my bad..did the click test on a subwoofer with a 9v, good call on the AAA battery..low amps, 1.5v, just enuff..

Well, it'll draw the same amount of current no matter the size of battery as long as it's 1.5 volts ... it's just a D cell will last a lot longer than a AAA battery ...

Ohm's Law states :
Power = Voltage x Current
Power = Voltage x Voltage / Resistance
Power = Current x Current x Resistance

So, if V = 1.5 volts and R = 4 ohms

P = 1.5^2/4
P = .5625 watts
0.5625 = 1.5 x I
I = 0.5625/1.5
I = 0.375 amperes