Do I need a relay?
 

I am running a few things to a switch panel that is below the radio in my civic. I will have a switch for all these: ignition, starter(momentary), fog lights, and led lights in the car, all on the switch. Will I need relays for any of these? What are relays for? I heard that the switches can get hot and catch fire?

Thanks

Re: Do I need a relay?
 

The electrical system of your car runs on 12 volts however individual systems work at different amperages. So if your switch is rated for the amperage then you don't need a relay. If you want to run a switch that is not rated for the amperage load then you have to put a relay in between the switch and the load circuit. The relay handles the amperage and the switch triggers the relay.

Re: Do I need a relay?
 

Thank you! You wouldn't happen to know the amperage on the ignition would you?

Re: Do I need a relay?
 

Your fuses will tell you the amperages.