Is there any reason I can't use one common ground wire?
Mike<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by PhilD:
Mike, the factory lights one switch and two relays and run two seperate wires.
Assuming you are using 55w bulbs, then 4 lights will draw 18.33 amps, most probably closer to 20 when heat loss, etc, is taken into account.
Nothing to stop you running just one circuit, but make sure your wire is plenty big enough. With a 7-10' run you will need 8 gauge wire to handle 20-50amps. You may get away with 10 or even 12 gauge, but 8 would be the safe choice. I would also use a 40 amp relay.
Personally, I'd go with two circuits, but nothing wrong with doing it on one, provided everything is big enough to handle it.<HR></BLOCKQUOTE>