Multi-Light Triggering:

If you have added additional lights beyond the lightbar spot lamps then this is a pretty cool trick for the electrically inclined. If your electrically challenged you might not want to do this. This stunt requires 2 driving light relays, soldering equipment, electrical tape and some patience. Total cost is about $20.00 and a few hours.
  
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Object Of This Project:
I have a set of H3 (55 Watt) driving lights mounted on my Cobra Freeway bars. These are extremely bright and also pull a pretty decent load on the electrical system. Because of that they are triggered by the high beam circuit.

  
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I also have a Suzuki lightbar which has the clear spots. I usually run these in the daytime only. For electrical reasons I do not want the H3's to come on at the same time as the Spots. I want the spots to automatically go off when the H3's come on and vice-versa.

This principle works off the fact that when you hit your high beam lights the low beam circuit shuts off. Conversly when you hit your low beam lights the high beam circuit shuts off. This makes a suitable triggering system to control the spots and H3's in a reverse parallel.

Getting Down & Dirty