Does anyone have a diagram showing how to wire a lighting system? I know how to do ones with a fuse, toggle switch, etc... But what is the deal with using a relay? BTW, i'll be mounting 4 medium sized lights on my roof rack..

 

relays are used when you need more power than a switch is rated for. The relay will have the main power in (from battery) and out (to lights) as well as secondary power in (from switch) and ground.


So you would run power from a constant hot or hot only when ignition is on (your choice) power supply (ie. tap into the fuse box) to your switch, then from the switch to the relay. Then you would run power from the battery to the fuse then relay and then relay to the lights.

 

Do you think running them with a relay would be a good idea?

 

It would likely be better yes, you would have to check the ratings on the lights and switch to know if you need to or not though.