When adding relays, make VERY sure that failure of any ONE relay will not take out both headlights, otherwise you are seriously increasing the risk of a crash due to losing both headlights simultaneously in the dark. That goes for fuses too. Relays are usually cheap, nasty things, which like everything else electrical can fail suddenly.
Tiger, you have posted this several times in the past.
Safety is great and I am not discouraging anyone from building the safest solution they can. However, consider for a moment that in most factory wiring schemes the headlights are not fused at all and that one switch contact supplies both high beams and another switch contact supplies both low beams. Using a single relay for high and a single relay for low is not inherently different than the factory wiring. The fuses represent an increase in wiring safety no matter how many are fitted.
Perhaps your phrase "ONE relay will not take out both headlights " is meant to suggest using ONE relay for BOTH high and low beams. That would be dangerous. However, all the schematics you find online and all the kits you find for sale will have at least two relays. I have never seen anyone (or any kit) where only one relay is used.
Edited by dklawson, 26 February 2016 - 01:05 PM.
