'Usually' you need a relay and a clean fused power line for high powered
lights.  The lights will draw too much for the stock switches or to be
added to any stock wire size powering anything else.

You also have to watch 'when' you have the lights on in most places.  If
they are classed as fog lights, they are only allowed on with the low
beams, if they are driving lights, they are only allowed on with the
high beams.  I know people that have been nailed for having lights on at
the wrong time.

You can have the relay power triggered by a tag on either the high or
low beams or running lights.   The relay's trigger wire draws almost no
power.

Here is one site on them:
http://www.classictruckshop.com/clubs/earlyburbs/projects/bosch/relay.htm

and this one:
http://www.danielsternlighting.com/tech/relays/relays.html

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
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