ok, there isnt any real good advantage to doing this, but I thought it would be cool so I went ahead and did it. I have a couple of H# halogen 100 watt off road lights mounted on my bumper up front and have them wired up so that when in 4H,N,4L they automatically come on and even if I leave it in 4WD when I turn off the key they go out and come back on with the key. I also installed an inline switch so that I could choose to ont have it come on automatically if I was somewhere where Id be blinding someone or something like that where the lgihts wouldne be a good thing.
materials needed (this is based on a 84 720 4x4 but the newer hardbodies at leats and probably most nissans have the little 4by light on the dash, if not you could probably figure out something to get them to work)
*1 accesory relay - http://www.jcwhitney.com/webapp/wcs/stores/servlet/EndecaControllerView?D=14sc9433y&Dx=mode+matchallpartial&firstSearch=1&catalogId=10101&Nty=1&Ntx=mode+matchallany&Dn=0+111&Ntt=14sc9433y&tmplframe=EndecaCategoryView&langId=-1§ion=body&storeId=10101&Ntk=AllTextSearchGroup&ss=10101
*1 toggle switch (if desired)
*about 20 feet of 14 guage wire
*assorted connections (butt splices, female spades, quick taps)
*inline fuse holder
-TOOLS-
wire cutter/stripper
wire crimper
test light
phillips screwdriver
10mm socket for battery terminals
(list may need adjustment depending on vehicle)
ok, since the switch on the transfer case just connects the groudn of the circuit for the light on the dahs, the easiest way I see is to do the same for the front lights. and since the groudn for the system is run thorugh long skinny wires only having to light up a tiny dahs light and IM now powering 200 watts worth of light I chose to use a relay as to not rely on the systems groudn for the lights
1) run a lead from the positive leads on your lights direct to the positive post on the battery using the inline fuse holder with whatever size fuse you need for your accesories you are running.
2)mount relay, I did mine under the hood so that I kept the actual grounds as short as possible, you might want to put it in the cab to kep it clean/dry, or find a protected area under the hood or wrap it in something when installing it.
3)run a lead from the negative post on the battery(ground lights will be using) to #30 on the relay.
4)run a lead from 87 to the grounds for your accessories/lights you want to come on when 4WD engages.
5)run a lead from #86 on the relay to a wire that is hot when the key is turned on(in my truck, when looking at the fuse block there is a larger wire that is yellow(dont remember what color stripe if any, but it is to the fuse block and is unused and that is the wire I used) to test simply ground the aligator clip on a test light and then touch the wires on the fuse block and then turn ket on/off and when the test light comes on with key and goes out when key turns to off that that is an acceptable wire to use)
6)run a lead from #85 on the relay to the wire that is ground only when in 4x4(this completes the circuit and opens relay when TC is put int0 4WD and connects the #87 lead to the #30 lead and grounds lights direct to battery) in my truck this wire is red w/ blue stripe, and it is in a large white plug with only 2 wires, other one is a blue wire(again maybe stripe, not sure il post tomorrow exact details of wires).
7)If you are working with a different vehicle, to get a starting point, insert key and turn on, attach lead wire to aligator clip on test light and put it to the positive battery post. there should be 2 wires coming off the T case by the shift lever. put the T case in 2WD, and then go under the vehicel and poke the probe end of the test light into both wires. the one that does NOT make the light light up is the one you want. to be absolutely sure of this go into the vehicle and put Tcase into 4WD and then go test the wire that did NOT light up the light and it now should. if so that is DEFINATELY the wire you want, wipe it of and note its color(should stay same color all the way through harness) go under dash and find a wire of the same color, and test wiht the light the same way as you did under the vehicle, should light when in 4WD and be off when in 2WD. attach the #85 lead to this.
8)now if you want to able to eliminate the lights while in 4WD then this is here the toggle switch comes in, put it inline the wire going from the hot when keys on to #86 terminal. now when switch is on lights come on with 4WD and when off light goes out and 4WD and dash light still function.
disclaimer. I am not a certified electrician or mechanic but i have a basic knowledge of electronics/mechanics/etc...
I am in no way guaranteeing this will not cause damage to any opf your electrical systems, mine are all still workign fine, and I dont see it causing a problems but just in case it does I am writing this so no one cries that I wrecked there truck. if anyone sees anythign wrong please post a correction or if you know it is safe to do please post so as well. and if you ever go wheeling at night and dont have a set of off road riving lights, get some, mine were only 30 bucks for the kit including a switch and all necessary wiring/connections and are 100 watts each, and after I installed them tok it out that mnight and man what a differnce, so much easier to see what the terrain si like ahead of me now before I get too close and get stuck.
i tried to post this in the how-to but dont have permission, how do I get this?
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