Normally Open or Normally Closed when adding switch to relay

Hi all,

recently bought a switch to use with a pair of fog lights I’m mounting to my car. I’ve ordered a wiring harness that allows me to turn the lights on and off without having the main lights on, my question is when wiring up the switch, am I better to connect a lug to normally open, normally closed, or common? i belive the relay is already normally open. any help would be great!


Hi Reily,

Usually the switch just handles the logic side and the relay switches the high current.

I’m not certain if cars are meant to be hooked up ‘differently’ to hobby electronics. These guides seem to be good: