M4RK

I bought a single 55 watt halogen lamp for $6 last night at wal-mart to use as an auxiliary reverse light. I thought a toggle switch would be cool to throw in the circuit to use the light for more than just when its in reverse but its not that important(not until I get a pair of lights).

anyways my question is, will it fry anything if I just splice this light into the + and - going to my reverse light bulb in the driver side taillight? I saw the writeup and lundhd but Im only using the one light(for now). Thanks in advance.

bad_4dr_sho

Relay is $5 and its better safe then sorry. Even though 1 55w bulb only draws around 5 amps. Installing a relay also makes it easy to add another light later. The way I'm wiring my 2 rear 55w lights are through a relay. Then I run the switch wire from the relay to a 3 position switch. The first setting is manual on (pure 12v source).middle position is off. 3rd position (works when you put it in reverse) run a small 16gauge wire to your reverse lights. It works great and doesn't cause any drain on the factory wiring harnesses.

M4RK

Thats a good point. Now heres another question for ya. I got a Hella 500 driving light kit a while back that came with a relay I ended up not using. can I use THAT relay for this reverse light setup?

Turbo X_J

Sure, why not?

ericfx1984

draws a little less than 4.5 amps.. assuming everything is perfect... so not really, but why chance it

5-90

Yes, since it's also a DIN relay that you'd probably end up getting anyhow.

However, the relay was included in the driving lamp kit for a reason - you should have used it. The switch isn't rated highly enough to sustain the running current of the lamps (2x55W = 110W. 110W/12VDC = 8-1/3ADC. The switch was probably rated 500mA-1A.)

Using a 55W lamp for an auxiliary reverse lamp should get a relay - trip it with the reverse lamp signal from the NSS, and you can also add a toggle switch so you can turn it on manually as well (that's what I did.) The NSS isn't rated to handle high-current loads either, I think it's good for about 2A.

M4RK

thank you, that help alot. As for using the relay with the driving lights, the wiring diagram I got with the kit was ****in crazy and a headache to read. I guess I should re-do all that as well. The only problem with that was, when I tried to tap into my drivers side headlight for the driving lights, it ****ed my headlight up and scared me into not wanting to run it with a relay.

5-90

Which is why I wire the auxiliary lights up on separate circuits, and only turn them on when necessary.

Fog lamps are wired to go off with the full beams on because people are too dumb to turn them off themselves.

Driving lamps are (generally) wired to only turn on with full beams because people are too dim to turn them off when they're not needed.

"Build a car any idiot can drive, and every idiot will drive one."

XJ Rat

These might help.

http://www.stu-offroad.com/electrica...8/backup-1.htm

http://www.naxja.org/forum/showthrea...lighter+wiring

http://www.lunghd.com/Tech_Articles/...erseLights.htm

Do you need a relay? At best, nothing will happen, middle of the road-strange things will start happening to your electrics, worst case-you will be replacing your Jeep after the current one burns down.
It is a little bit of work, but yes, the relay is worthwhile.
FYI - the relay that came with my Hella 500s was inoperative. It went in the trash. What do you expect, it had "made in Mexico" stamped on it.

On my TJ, I followed the lunghd example and had the lights come on automatically when put in reverse + the manual switch was there. Worked like a charm.

bad_4dr_sho

More then likely your headlights went crazy, because your driving lights were putting power back into the headlight system. Current only likes to flow one direction. I have a 99 Tahoe which I wired to run the headlights and highbeams at the same time. I also used a relay, but I put a 99 cent Diode (from radioshack) in line with the wire that jumps off your factory headlight harness and goes to the aftermarket relay. This allows current to flow only one direction and will probably solve most of your issues. Make sure you wire the diode in the right direction, if you get it wrong, nothing bad will happen just the lights wont work and you have to switch it.