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Wiring Question, Adding Reverse Spotlight

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theleisure

theleisure

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Hi guys,

The gearbox I'm about to install has a reverse light switch that I'd like to take advantage of. I bought a spotlight that I'd like the switch to activate but I have almost no experience with wiring. I am able to read a wiring diagram and fix minor problems but I don't really understand them enough to add to what's there. My 66 sprite didn't come with reverse lights so I'm not sure where to tap into my harness. So you know what's there, the reverse switch on the gearbox has 2 wires coming out of it right now, as i recall they're both green but I might be wrong. Any input would be appreciated.

Thanks
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I'd tap into the switched power at the fuse block. If I'm looking at the right diagram in my Haynes manual, it should be a white wire from the ign switch to the fuse. I'd come off this point, add a fuse, then wire to the switch, and finally from the switch to the backup light. The other terminal of the light is grounded, of course. Use at least no. 14 wire and the fuse depends on the current drawn by the light--if it's a small light, like a tail light, I'd use 5 amps, otherwise 10 amps. Of course, route the wire where it won't chafe on anything or get snagged--this probably will require more thought than anything else.
 
Can you define "spotlight"? Like a Lucas 576, or a smallish rectangular jobbie?

The gearbox switch will control when the light comes on, but you need power to it and from it (to the spotlight) and a ground for the spotlight itself. Preferably fused and ignition switched. I don't have my Lucase code handy.

If this were mine, I'd probably use a relay, depending on how large of a spotlight. As mentioned, fuse the circuit at 5 or 10 amps
 
If you're talking reverse light (as opposed to spotight - which seems big) I had my actual reverse lights removed when I had the bodywork done as they (the square ones) seemed a paricularly inelegant solution. Instead I have a signal light from a motorcycle which hangs under the bumper and (to my mind at least) looks very pretty. When I came to install it at that end, I doscovered on the split bumpers (don't know about the full length) that there are actually holes in the bracket that fit the light bracket perfectly - no drilling. I then ran the wire through the body along with the license plate lights and it fits easily.

Basically you need a power feed - the suggestions so far are great - the actual feed in later cars runs off the same line as powers the brake failure light circuit. (don't know if you have that)

This power feed will attach to one green line on the tranny switch (doesn't matter which as it is a switch) the other green line from the tranny will go to the rear of the car into the light and the second line coming out of the light will go to ground back there - probably against the nut on the tailight unit. Hope this makes sense. I can post a picture of what mine looks like if you are interested. They were a pair of generic lights at my handy motorcycle shop - cost about $20
 
Thanks for the suggestions. I tried to post a photo in my first post but I guess I haven't figured that out yet... Here's a link to a picture of a rear spotlight like the one I'm installing. It's big-- 5" I think. It's going to be mounted on a bracket between the license plate and the right bumperette. I'll (try to) post pictures as I go. Who knows, maybe it'll look stupid but at least I'll give it a shot.
 
Check the laws in your jurisdiction. Such lights pointed backwards are likely illegal.
 
Check the load on the lamps you intend to use. If its anything more than a 1157 type of bulb I would consider running it with a relay. I would think the tranny switch could not take more than a tail light bulb or two.
 
Definitely use a relay...
 
I agree RE: the relay. was thinking about the size and possible legality as well as the fact that you could seriously p*ss people off with a reverse light that bright. One thing you might consider is a "factory" reverse light plus the spotlight. I would then put a bypass switch on the spotlight to use only when you want. Then you have satisfied safety/ legality and coolness.
 
I used to have a white fog light mounted center rear below the bumper on a car I had back in the early 80's. (I used to back up a long dark driveway nightly so the extra light was a big plus!)

This light was activated by a relay, triggered by the existing reverse lights.

To twart any possibility of getting a ticket I used to carry an elastic fog light cover, just in case I ever got pulled over by a cop having a bad day...

"Cheers!" :cheers:

-Bear-
 
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